Will a 1976 Corvette C3 Hood fit on a 1978 Corvette C3.
yes they will
Yes, the headlights should be completely identical.
Yes. The 75 will have the plastic bumpers, so there will be subtle cosmetic differences, but, it will work.
will a 1985 corvette hood fit a 1993 corvette
yes it will fit
Yes, they are a direct fit. TOM