O-W, the tubing is part of Crusty's setup, not mine. I'm sure it's a size you're readily familiar with. As for storing extra presses, I just C-clamp the ones I'm not using to a nearby hunk of shelving until I need them, then swap them out in a matter of two minutes.
Rockridge, you came up with a few of the same ideas I did, and outlined them better than I would have. A template that included locations of mounting holes for most of the current presses would be an awesome idea! If you look at the first picture in the opening post above, you'll see what Lee has done.......you get one wood mounting base already drilled for all their standard presses, and two more blanks. Figure out which holes you'd use, copy their locations onto a blank, drill it out, and mount your press. A paper template (as you pointed out) would be even simpler, and a lot cheaper. Simple is Good.