Thanks for all of the helpful responses!!
Ive tracked down a place I can purchase just the shim kit at, I will be ordering a new set (pretty cheap, so its not a huge deal).
The fluid level in the MC was halfway between min and max, I upped it to be 3/4 of the way up from min to max, just to see if it helped (it didnt).
The slides you guys are referring to are the actual pins inside the rubber boots, correct? Looking quickly I didnt see an easy way to remove them without destroying the boots, any advice would be helpful
BTW, funny you mention DOT3 + hygroscopic + 'vette brakes. My dads last Vette was a '72 with the 4 piston sport calipers. Used DOT5 (!!!) fluid. Ultra expensive, but I think its basically pure silicone. But my dad taught me that brake fluid sucks up water, one of the few things he taught me that I actually listened to!
Thanks again!
-Chris