I put the chevy cylinders in last Friday and have had a bit of a spongey pedal since then. . Have tried backing up fast and hitting brakes hard to adjust the rears out, seemed to help some, so time will tell.
As for getting the drums off, I had both rears in the air, truck running in 5th gear at about 40-50mph and then hit the brakes hard. Drums popped right loose. Make sure you have 2 lug nuts on or your drums will be gone.
May take a couple tries, but it does work when nothing else will.
Brad