I looked again and the inside of the frame has to be 28 inches, not the outside. So that means I only have to pull the frame in 2 inches per side.
I have a fox body firewall forward frame section, so I'll take pictures later.
One thing about an SLA, the shock towers will be removed. This may give a couple inches of more room for the headers.
Also, the inside of the frame needs to be 28 inches, and with the length of the a-arms, the turning radius may not be affected much by 'stepping' the frame in to mount the upper control arm and the cross member.
I do realize fitting the C4 suspension inside the fenderwells is only the very top of the box of worms, but one step at a time. There is a good chance none of the factory parts from C4 will be left by the time I get done.
The messurements I've found leaves the question, would the stock C4 front suspension be good for a new edge or S197 mustang SLA. Both of which are very close to the track width of a C4 vette. All you need to do is get a Coil Over set up and figure out the rack and pinion.
Doesn't matter who makes it, as long as it's fast!
'99 Saleen S/C 281, 2007 Shelby Gt (track whore), 2010 427R daily