275 required lots of work on my car for several reasons.
Had to work when racing, so full suspension movment without marking the tires to avoid tech problems.
Car had been hit in one fender so instead of just the light roll it had to be cut as the layers hadn't been welded together.
Exhaust had to be solid mounted at the hagers as the force of cornering on DOT Rs was moving them literally inches into the tires inside sidewall.
Tried putting camber back in w/ camber eliminator in place at rear to tuck tires, but found the limit.
Narrow 275 like NT01, RA1 and RT-615 etc will fit, wider 275 tires won't
Here is the thread on the fitment where it fit, it didn't fit and we made it fit
http://www.rx7club.com/showthread.php?t=772831