All good information here. Also, I know this sounds dumb and you may have done this already, but remove the pads and look them over. I had a small leak on the inside piston (4 piston calipers on my 69) and it would leak enough to soak the pad over the winter but not enough to leave a puddle or tell tail. I cleaned up my rotors, replaced seal and pads, and much better. I had my power booster take a dump many years ago so went with manual discs. Not pleasant and kept me from enjoying the car. I just sent booster out for rebuild. Hoping to put many more miles on it this season.