as for the mounting, why not glass in a hinge at the front edge that you could rivet to the frame with a catch at the rear edge, easy access, just undo the catch and swing open and if you need to you could easily drill out the rivets, you could even weld a couple of small bolts to the frame and bolt the hinges in position with the hinge
just a thought, easy open and close without breaking the mounting pins, they are repro`s anyway, they can look original from the outside and be "improved" on the inside
cheers
troppo