how to repair

I usually like to re-engineer things - especially older stuff like this - test fit what you have and go from there - if you can see light, it'll probably leak and needs more weather strip (or something). There's no easy answer here but I will say this, are you looking to make it look A+ resto or are you more concerned with getting it to work for you? The answer to that can aid you down a certain path. I rebuilt my Harley about 10 years ago - correctness be damned, I wanted it to last - so I changed things and used different materials to make things fit the way I wanted... "incorrect" nuts and weather strip...