Sorry evad, sounds convoluted. As Fred noted in the other thread, you'll get corrosion in between the two if you (temporarily) bolt them together (as in running your webbing through both together). You'll need to pry them apart and rinse them well after your dives. It sounds like a PITA. If you want a heavy plate, get a heavy plate. They work great. If you want a six, use a six. To put together two sixes seems like you're solving one problem and causing another, mostly maintenance-based, issue. I'd sell the 2nd 6lb plate as an extra and buy a heavy plate if one works for you. I'm using a 12lb FredT plate that is excellent for real cold water/drysuit use.
