Slick Sand and Featherfill G2 are both good options. I prefer the G2 for how it sprays, but both will work. Before any primer goes on though, the key on is getting the existing paint and old bodywork off so you can see what you're really working with. I've uncovered a lot of prior work on Corvettes, including part of a front clip that had been replaced on a mostly original '65! One that has been wrecked and repaired by a shop that wasn't thorough may have some surprises underneath. If I was taking it on, I'd strip it down to a stable substrate and confirm there aren't major structural issues before starting on everything. From there, go to a high build polyester of your choosing and start blocking it out. Being in California, you might also consider Duratec vinylester primer. On the clears: Pro Air is on the soft side. It's a good factory replacement clear, and in the Lesonal line, EcoClear LV and Universal Clear are even softer. For a car that gets driven and washed a lot, that's worth knowing going in. Superior 250 is the best clear in my opinion, but it is very challenging to spray. What you're describing, self healing, gloss retention, lays out without a cut and buff, is attainable, but it takes great equipment, skill, and money, not just a good gallon of clear. The grand helps with the material, but expect things will add up quickly - both materials and time. If this were my job, that's the order I'd run it in: strip it, confirm it's a good base to work with, high build polyester, lots of blocking, then pick the paint materials based on budget and realistic expectations.