First time to attempt working on a hydroboost. My 1979 Chev. C30 unit was leaking. Units are not available for my truck. I bought your seal kit, but didn't know about your special tool. You should list it as an option along with the seal kit. I have a Craftsman 1/2 inch drive chrome plated 30 M/M socket that is .004 of an inch smaller in diameter than the power piston. Taking it very slow and careful, lubing with a lot power steering fluid, put it back together. Thanks for the inexpensive fix!