Hello Scott,
I had a giant C-frame made for my hand squeezer, something like 20 inches deep, from one inch thick steel plate. I had a couple of tabs welded on the underside so I could sit it on the work table. Squeeze with one hand and move the part with the other. Very quick and effective. I could still change it out for the normal C-frames for the hand squeezer. The Squeeser just barely made it through the project though.
Make it even bigger than mine, especially at the curve in the back. Sometimes the dimple dies would bind because the frame would still give a little.
Another very handy tool is a dimpler for the pneumatic gun. Cheap and also very quick (but noisy of course).
Regards, Tonny.