It’s the classic car reality: the beloved ’60s muscle car from high school rusting away in a field. This was the sad truth of our ’67 Firebird—that is, until the day we rolled it into our new shop and began the journey of getting it back on the road.
Having recently replaced the floorpan while documenting the story for HPP’s sister publication Car Craft, the trunk pan was next on the list!
Most restoration projects are learning experiences, and we learned a great deal with this install
1. If the trunk lid has been removed from the car, reinstall it, then check, measure, and
There are two options for dealing with trunk floor issues—repair or replace. Both have their pros and cons. Installing a mid-section patch panel is far easier and quicker than doing a full trunk-floor replacement, but we opted for the full-replacement piece as we are doing a complete restoration and are already replacing major panels, including quarter panels, the taillight panel, and the roof. After seeing the incredible result of doing a full floor-pan replacement on this classic Poncho, we viewed a full trunk pan replacement as a logical step.
Dynacorn’s full trunk floorpan (PN 1046B; $327.47) is tooled from modern automotive-grade alloy, not a universal-grade steel like many patch panels. The alloy is elastomeric, so it bends without losing strength.
Dynacorn says it’s selling as many full trunk pans as trunk patch panels because as Firebirds are becoming rarer, restorers are taking on bodies that are severely decomposed.
The install required basic welding, cutting, and mechanical skills. With a plasma cutter, a TIG welder, a drill, chisels, hammers, welding clamps, and help and advice from some friends (Jennifer LaFever, Jasen Taylor, and Terry O’Hara), the process went smoothly.
Knowing that it’s critical to support the unibody F-body at the right locations so the structure of the vehicle is not altered, we removed the Firebird’s rear end, and supported the vehicle on four Craftsman 3-ton jackstands, placing one jack at the front and rear of each framerail. The front subframe remained on the car.
It’s a good idea to take photos from many different angles, and we followed this rule from the beginning to the end of the project. This way, once it was going back together, if we had a question as to how something fit, we referred to the photo. We took our time with this step and were very thorough.
We followed two other rules throughout the project. We double-checked our measurements, and we retained the cutaway parts until the install was completed. It’s handy to have them to refer to if needed.
Years of hard driving, burnouts, and the occasional accident will stress and stretch the body. As panels are cut apart and as stress is relieved from the metal, things start to move. We welded in braces across the interior of the vehicle when installing the floorpan. We left them in place and added additional bracing from the wheelhouse to the trunk jam for the trunk-pan install.
The rust was confined to the gas-tank area, but it’s hard to know exactly what you have until you start cutting. Once the main-trunk-pan layer was peeled back, it was easier to see the extent of the compromised metal.
We marked the framerail areas in chalk. It’s essential to keep the framerails intact. The easy way is to create a guide on the top surface by getting under the car and either plasma piercing or drilling a series of holes around the framerails, leaving ¼-½-inch between the hole and the edge of the rail. We had cut off the taillight-panel support bracket and put it aside for use on the new trunk pan.
Most restoration projects are learning experiences, and we learned a great deal with this install. Admittedly, the trunk pan doesn’t get noticed often. Nonetheless, it plays a critical role in the structural integrity of our Firebird, in that it’s a keystone piece that holds together and supports the back end of the car.
Editor’s Note: JoAnn Bortles is an award-winning custom painter, airbrush artist, and book author with over 30 years of experience in the automotive industry. Her work has been featured in Street Rodder, Hot Rod Milestones, Hot Rod, and other automotive publications.