pulling to the right

An update... and a question.

After the car sat overnight, I jacked up the front and tested the spin on the wheels; at first, I thought the tires weren't off the ground. But no, they were that tight! I took the car back to the mechanic, with a printout from the manual on how the brakes should be adjusted. Still... the car pulled to the right.

He suggested that perhaps a proportioning valve was needed, since I had him install a dual M/C... I pointed out, a proportioning valve affects the balance between the front and back, not front to left - and besides, it's needed when you have discs on the front and drums in the back, not drums all around as I have. I pointed him to this thread... And something clicked.

He put the car up on the lift, and checked the dimensions of the wheel cylinders (which the shop had ordered) - they appear the same on the outside, but the insides were different diameters! One side is getting more drag that the other, which accounts for the pulling.

New cylinders have arrived, and Tuesday I drop the car off for the installation. But, here's the question:

After the car warms, I still get a screech on a hard stop. Could that be explained by the difference in drag? Or do I still have a (different) problem?