Just so you know, here is the current bench:
The powder measure, and case trimmer are currently mounted on a board that comes off with wingnuts. I'll save the upper shelving. They just sit on top of the surface. I'll probably maintain the same dimensions as the old table. Mostly, I'll be replacing 2X4's with 4X4, 3/4 inch plywood for the 5/16ths surfaces and using screws to replace nails. The original builder was a lawyer, not a carpenter.