I may solve the matter and build Rear Shock Tower Braces that are adjustable for each application.....Use a threaded rod and jam nut to secure to correct width for you car. Anyone interested?...projected cost is $55.oo to $60.oo dollars right now.........as I find a faster way to assemble them.......price will drop.
I will modify my Thunderbird shock braces to fit Fox body cars..43" with bolt on angle stock.........3/8" grade eight bolts/etc. included....sticker too.
Everyone has an opinion on these..........both pro and con.......I have sold dozens for the MN - 12 cars......with a Fox body using unibody..any additional strength is a bonus.
Ok.it's the type that bolts through the thin body panel rather than into heavier metal of the shock tower. the metal is too thin in my opinion to afford you much of a gain or noticable improvement. Mine require drilling holes for mounting in the heavier tower.
IF..you were going to keep the rear brace...I could provide you with a 2" x 6" x 1/8" steel to use as a back up plate to make the connection more secure. Bolt in on the tire side of the fenderwell.