Super clean and smooth looking car you have there. And I think 18"s are perfect on it.
Ok...so you've been talking to Corbin at KORE3. If it where me, I'd would be looking at the C5/C6 setup he has. I had basically the same setup on a 67 a few years back and it was awesome. My buddy Jeff runs it on his 68 and it will stop on a dime...or whatever the Swedish equivalent of a dime is.
Both Jeffs car and my old one have the ATS spindles on them. A wonderful upgrade. I'm sure Blake and the crew at Speedtech will be happy to set you up with a pair. Corbin might also be able to supply them.
Hope this helps a bit.