barracuda and barracuda s??
Please clarify "Clone".
If you simply want it to look like a Formula S, get the correct emblems and have the cut outs put in for the exhaust exit on the rear valance (they were stamped out on real S cars).
Really the difference is not very big......
S cars had heavy duty suspension (Shocks, rear springs, front sway bar and torsion bars) Engine package (340 or 383) and an 8 3/4 rear end.
I think slapping S emblems on a car is silly (most people don't even get them in the right place).
If you want to make a FULL ON "Clone" you would be better off finding a real S car and take a butt load of pics.