i did all this crazyness some time ago. found the g-adapter, got a 6x8 backs, machined the g-adapter with a dremel so the opening was way bigger than needed and i get bigger negatives but not of any significance and the edges are all fuzzy wuzzy. so i started out hoping for the perfect 6x8 back ive learned its not happening with the rear opening size of the RZ. might be an excuse to get an RB. if only my 50 ULD would fit on an RB at infinity focus.