So I put Shelby style taillights on the 66 Mustang. Rather than installing them on the exterior of the rear panel I cut holes and installed them from the interior of the trunk.
I watched several videos of people doing this. I used a few ideas from them but overall i did it my way.
I started by creating a template out of flat cardboard. I then transfered the shape from the template to the panel of the car.
Using a jigsaw i cut the holes. I fit the bezels to the holes. Using a flapper disc on a 4.5 grinder I carfully ground off a small amount to get an exact fit. It is much easier to always cut a little smaller and enlarge it to the correct size.
I turned the bezels backwards into the holes and marked the screw holes. Center punched tge holes and drilled them. I cut the heads off #8×1.5 screws and welded them into the holes. I also welded the holes for the original taillights shut.
I dry fit the lights everything fit perfectly. Once car is painted I will use strip caulk to seal them to the body.
I also sanded the bezels with180 grit, primered, and painted them black.