I also welded a new full trunkboard in complete with extention panels (unfortunally the pictures which I had taken didnīt come out that good..sorry..)and I welded the new floorboards in as well as new RH outer wheel house and RH rear quarter.
I hate to use filler so welding in the quarter panel was done so that it needed no filler at all..It costed me 1 whole day to weld a little...let it cooldown..weld a little...let it cool down... ect..In fact I welded now about 8 quarter panels in firebirds and they all fitted very good except for a little bodywork which is alway needed to make that perfect fit.
I rolled the car over (of course on the side that still had the old quarter panel)
cut out the convertible reinforcement bracket, sandblasted it and welded it back on.
replaced the fuel tank braces and started with the frame rails, I used zinkplated metal here which was about 0.12" thick (in metric 3mm)
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