Yeah, unfortunately (or fortunately depending on your view), the drop spindles available require you to install disc brakes. You can't use your drum setup.
As for the rear, that throws a kink in things. I don't think I've ever seen a '65 with only leaf springs. Auxiliary leafs yeah but, not straight up leaf springs. Are they on top or below the axle? How's the rear lowered right now?
Options for leafs would be having a set made from Eaton springs
Eaton to get you a little lower and better ride quality. If it's not low enough, you could add a 1 or 2" lowering block.
AirRide also makes a setup for leaf spring vehicles called AirOverLeaf.
Air Ride -David
