Sounds like you need to find someone who can actually DO an alignment on one of these cars. I mean a REAL alignment, not just setting the toe. From you description, you may need to have more caster in the front than what it has now, since it seems to want to go into the initial turn, but not straighten out properly.
Rear alignment on these things is a pita to begin with, and it's getting harder and harder to find someone that CAN do them, and WILL do them. A lot of the "Corvette" shops don't really have anyone that is properly trained on the '63-'82 cars, regardless of what they may tell you. Since there isn't a big call for them on a daily basis, they don't bother. It sucks, but that's the truth of it. Too bad Chris(Petris) isn't still in Florida.....he could fix you up and do it RIGHT.
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Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"