Phoenix Rising

Restoring a Firebird with aftermarket steel panels

Story and Photos by JoAnn Bortles

After getting tired of seeing my favorite model of Firebird decaying every day, I decided to do something about it and planned a complete restoration. At first glance, half the body panels would need replacing. But once I got into it, I had to embrace the harsh truth that every single body panel — floor and trunk pans, quarters, taillight panel, valances, doors, fenders, hood, outer wheelhouses, trunk lid, lower firewall, and even the roof — would need replacing with Dynacorn panels. There could be no shortcuts. It was either all or nothing. I knew it would be a lengthy process, but hoped the body and paint could be done in three months, as the car was scheduled to be displayed at the SEMA Show that fall. We had four months and needed every moment of it.

The measuring tape is your best friend when replacing body panels. Measure everything from every angle, before and after the panels are replaced. Take the time to draw a sketch of each panel and how it fits, then write in the measurements. It takes hours of checking measurements and fine-tuning the alignment before a panel is
welded on.

Now this is the fender-to-door gap we were looking for, after many hours of fitment, which included changing the positioning of the door by adjusting the hinges, and changing the position of the fender using the slotted mount holes that hold the fender. We also shimmed the bolts, and added metal to the edge of the door and fender by welding wire onto each. Then finally applied SEM Carbo Fill (body filler) to fine-tune the bodywork.

Here, the quarter-panel is clamped onto the drip rail. The drip rails were an area where we got lucky, as they were in pretty decent shape. They attach to the inner skeleton of the car and we used them to help line up the quarter-panels and roof. You can see the plug weld holes have already been drilled along the quarter- panel. Always drill the weld holes before tacking on the panel.

While I had done a number of restorations over the years, I had never attempted a restoration of this magnitude. What follows are the major steps involved, along with some practical tips for anyone else considering a similar restoration. Just keep in mind that reviving a classic car often requires a lot more than you might expect.

We used a variety of techniques to get through the spot welds. While most of them were gouged with the plasma system, others needed to be ground, as the inner skeleton of the car was right underneath. Along the sail panel we used a cutting wheel to carefully grind away the spot welds. Then the metal was separated with a chisel.

Here, the guys lift the roof off the Firebird
so it can be replaced with a fresh panel.

Here’s the trunk floor that will be replaced. The first step is to take several measurements, so we will know if there needs to be any adjustments made once the trunk floor has been removed. If the quarter panels are left in place and the frame rails are in good shape, it’s unlikely that these will change. Measurement 1 will go between the inner wheelhouses. Measurement 2 will go from the inside of the right frame rail to the inside of the left. Measurement 3 will go between the bumper mounting points on the rear quarter panels. Also make sure to remove any supports and brackets that will be transferred to the new panel. The yellow arrow indicates the gas neck filler support that was removed prior to cutting.

The driver’s side fender door alignment looked pretty good at first, but as we began to fit the rest of the panels, the gap grew bigger.

No matter which brand of panel you go with, all of them will need a little work in order for everything to fit properly. One thing to take into consideration is the fact that most of the vehicles being restored are over 40 years old. The metal bodies and panels will be changed by over 40 years’ of gravity, decay, and road wear and tear. Even if the replacement panels are perfect, the structure they are mounted on will not be. That means doors and fenders might not line up easily.

Here I’m using a Hypertherm Powermax45 Plasma System to rough cut the floorpan, running the torch along a piece of angle steel to get a straight cut. Make sure you know what’s under the surface before doing any kind of cutting. Sometimes there are bracing pieces that are bonded from the factory under a panel.

This is the way it should look at the rear of the car, even gaps, everything fitting cleanly together. This was achieved after countless hours of adjusting the fitment of both quarters, the taillight panel, the rear valance, the doors, and the trunk floor. These panels were held on by screws and tack welds, that way it was easy cut a tack and adjust. Nothing was solid welded until after all the fitment was complete.

Here, the front of the quarter panel is clamped to the inner panel and the B pillar. Note the plug weld holes, which make it easier to see exactly where you are on the B pillar. Proper fitment of the quarter panels takes hours, as their placement is relative to so many other panels.

For the Firebird, we went with all Dynacorn replacement parts. Some panels fit perfectly, like the one-piece floor pan, the trunk pan, taillight panel, kick panel, roof. Others needed a little help. And OEM-brand original parts do not guarantee a perfect fit, which is something I’ve learned the hard way. Overall, I was very happy with the quality of the Dynacorn parts. And their delivery time was excellent. Of the over 40 parts we ordered, less than four were out of stock, and only one was back ordered for more than a week.

It takes a variety of tools to replace a panel. These were used for the roof replacement. Note the Evercoat Panel Bond. While the front and the back of the roof were plug-welded to the inner framework, the sides of the roof were panel bonded. In newer car assembly, many parts are not welded on, but instead bonded together. Don’t overlook modern technology when working on classic cars. There are some attachment situations where panel bond products are as good or better than welding, especially in
nonstructural situations, where the metal is very thin.

To add metal to the edge of a panel, first find a wire that is a little bigger than the area that’s being filled, bend it to fit the shape, and carefully tack it to the edge. Then weld it on, one little stitch at a time. Allow the metal to cool before welding each stitch, so you don’t burn away the little wire.

A quicker way to remove spot welds

There were hundreds of spot welds that needed to be removed on this resto. Using a plasma system to gouge away the spot welds shaved countless hours off the job. The Hypertherm Powermax45 XP plasma system is set at 10 amps and the air pressure is adjusted down to the lowest it can be, and still indicate green on the front of the machine. The process is repeated on the other side of the weld.

The closeup photo shows the “grooves” around the top layer of metal of spot welds on this firewall panel. The metal is thick, yet I could cleanly remove the top layer without going through the second layer. The arrow indicates where you can see the actual separation gap between the layers and how the removed metal did not wash into that gap.

Start off by placing the end of the torch just beyond the edge of the spot weld. Next push the trigger and start the arc, warming up the metal until it glows. This happens fast, in a microsecond.

Once the metal of the top layer starts to melt or burn away, flick the torch up, then back down. Watch carefully as the pressure from the arc literally “washes” away the top layer. Flick the torch up and down, pushing the molten metal down the groove you’ve created. Then move to the other side of the spot weld, and repeat the process, creating two L-shaped grooves around the spot weld.