I decided to chop off the seat hinge. I thought I'd integrate a seat pan utilizing the ordinal hinge but had too much fun with my new toy...
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Got a little carried away and ground the raised/pinched steel on the stamped shock mount area too. There.
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Next? Well, I want to make sure about the hoop length so I can start fabricating a seat pan out of 0.080" ABS plastic, maybe steel if I can scavenge some parts. I can also fab some small triangular pieces to integrate the rear turn signals and continue the slope of the angled part (per Bru-tom's build above). I need to find someone who can help me do a little welding...
Behold, the slowest motorcycle rebuild has not given up yet! Still going, slowly but surely. Happy Memorial Day weekend!