I can't lend any sort of helpful repair advice, since I've got three bodies (SIX, SIX M/M and Super 66), each with an issue of some sort. Same goes for the lenses. I'd love to send them all to Ross and tell him to have at it. But I love this system. The light seals you ought to be able to replace with stock stuff. Wish I had some ideas about the back latch, but I'd say you're on the right track. (Ross may have spare parts for this, you know.)