I'm thinking about a Metolius Slim Gym for my apartment. I've read the reviews that say it's cramped, but it's all I have space for. My problem is that the wall where I want to put it has no studs (even at the edges of the doors). I am, however, reading about 1 1/2" of ceiling joist sticking down into the wall with my studfinder. If I screw the top end of a piece of 3/4" plywood into that inch of joist, then mount the hangboard on that, will it hold my 190 pound arse? Has anybody else dealt with these that can give me advice?