When I pressed in the second bushing in the upper A-arm (the first one is not a problem), I first cut a piece of pipe to fit inside the A-arm with an ID slightly larger than the OD of the bushing. I then cut the tube in half along the center axis, creating two half-circles. I installed one of them into the A-arm, installed the through-bolt and put another piece of tube under the first bushing already installed (and facing down on the hydraulic press table) and then started pressing in the second bushing. This way the load was transferred from the upper bushing to the press table. I'm sure there are other ways to do it as well.

Kåre