I've never pressed pistons before, that's always been a "let the machine shop do" kind of thing. I remember seeing it in several years worth of FSM's where there was a special fixture needed to do that. I do have a 12 ton press in my garage here but no fixture.
The last 360 magnum I did, I had to have bored so they had to replace the pistons and I remember returning to the machine shop with one piston/rod because they had it backwards, for the tab side of the rod and cap to face the right way, the notch on the piston would have faced back not forward.
I also know they have an induction heater to heat the small end of the rod to expand them so they can basically drop the pin into place. I don't have that either.
So how do you press pins without the right equipment?