[Lynn]

Messed with one years ago. Like most items, the rebuilts are so cheap, it is way more cost effective to just buy, so that is what happened over the years.

Never monkeyed around with an aluminum housing WP.
I wouldn't worry about that interference fit. Stamped steel moves pretty easy. Not like a damper.

As for controlling the shop press, my only advice is to go slow, use some penetrating oil for lube so it doesn't "jump" too much at a time, and tap the press with a hammer lightly while stroking. Guessing you have plenty of steel blocks and plates to support the housing.