IIRC, their ad shows you receive one mounting pad predrilled for Lee presses and they include two more pads that are undrilled. I assume you can order as many extra mounting pads as you need. I have mixed feelings on this mounting system as I have permanently mounted my single-stage and use woodscrews on the benchtop for all my accessories which includes my Star progressive. Had I not set up my bench this way, I would give this more consideration.I have been looking at it also and it's a very reasonable price. If the thing would work with all my presses including my mec sm77 i would be all over it!
EDIT: I take it back. They've published it as templates for their presses: http://www.leeprecision.com/cgi-data/instruct/TMPMASTER.pdf
Send it to me i'll give it a good home I have been looking at pats designs also and they do appear to be extremely well built.I purchased this system and am more than a little disappointed with it. They only supply 3 mounting bolts when 4 are really needed. The wood insert plates do not really mount completely in the mounts. I was lucky if I got 1/8 of an inch under the brackets. Not very much when you start beefing on the loader. Only one mounting plate is drilled for all of lee's reloading equipment. They should have had them all drilled with the ability to purchase a blank mounting block if you need to. I scrapped mine and order a PatMarlins system. It is made of metal all the way and if you let him know what you are going to mount, he will pre drill the inserts. His system is many times more stable than the Lee Bench Plate.
I purchased mine so that I could travel and not have to drill holes to reload. I have mine mounted on a sturdy piece of wood and just clamp it to a table when I reload.
Could you post pics? You have me thinking on this now.I made my bench top out of a double layer of 3/4" plywood. Before setting it, I cut two 10" squares out of the top layer each 1/3 of the way across... then cut two 11"x12" squares out of the bottom layer to match.
Then I cut several other 10"x10" and 11"x12" pieces, and made interchangeable bench plates. It works great and has lasted over 20 years now with many more to come.
But I would have just bought a RockDock if they were for sale back then.