This piece was in a bunch of parts that I got with my 34 five window. I can't figure out where it goes. I took it down to Vintage Ford and they couldn't help either. I think it goes in the trunk area but I can't figure it out.
Goes inside the rear panel below the trunk lid. The latch panel connects to it, and it strenghtens the whole tailpan-quarters-floor area. Same part on three-window, five-window, roadster, cabriolet.