[ischmitz]

If you pump the pistons out without the pad installed or with a much thinner spacer installed you should be fine. The trick is to push the piston in just enough so that you sort of have to wedge the pad in there to get it installed. That's preload the piston and prevent it from retacting too far every time you release the brake pedal.

I didn't use spacers. You have to do one at a time. I was watching the piston while a second guy carefully depressed the brake pedal. As soon as the piston came out far enough so that the pad would not simply slide into the caliper I used a big screwdriver to carefully push it in again while putting the pad in place. Once the pad got started I had to tap the pad so that it would slide in. No need to use different cheaper brake fluid here. You can get all four calipers bled and a hard pedal with about half a can of ATE if you get the hang of it.

Ingo