Yes.
Yes.
Yes.
Not exactly. '75 used a "dual securing clamps" for each T-Top. '79 T-Tops were redesigned with a "single securing clamp" for each side.
No. There are three different tops for the C4 Corvettes, 84 to early 86, late 86 to 88, and 89 to 96.
Yes
Yes. The 75 will have the plastic bumpers, so there will be subtle cosmetic differences, but, it will work.
Yes, they were indentical
Yes
No
will a 1985 corvette hood fit a 1993 corvette
No, the 1974 Corvette frame is NOT the same as a 1975 Corvette frame. I have had customers modify it to fit, but you would have to change the rear kick up or adapt a 75 and above rear bumper assembly to make it work.