BMW update.
Got a ride home, hooked up the trailer, back into the city to get the bike, and then back home again. Great use of my evening, hours solo retrieving around an ungrateful dead bike. Turns out that the piece of in-tank fuel line I'd used out of some Delphi fuel pump kit I had on the shelf was a piece of ****. The line had turned to sponge and blew off the fuel filter which explained the non-running condition as it is hard to get fuel pressure when the pump is pumping back into the tank. So, I replaced the fuel hose with some proper SAE 30R10 rated fuel hose and put it back together. While it was apart, I replaced the hall effect sensor (mine was remarkably in good shape, even at ~27 years old) and changed the alternator belt.
Voila. Back in business. Put it back together and took a lap around the neighborhood. Went inside, made dinner. Around 11pm and headed to bed..."man, that's weird.. something smells." Opened the house door into the garage and was hit by a wave of gasoline fumes. 5 or 6' puddle of gas under the GS and it was
actively running out like a water fountain. Like, gasoline streaming out of the bottom of the tank. More F-bombs. So then it was a race to see if I could empty / siphon the gas tank faster than it was draining onto the floor. So much fun!
Turns out the fuel pump flange sealing o-ring slipped out of the groove during installation and had been cut. Swelled up and held long enough for that test ride but then finally gave up., Not only that, but BMW's fuel pump mounting plate is prone to warping if misaligned. Awesome. Yesterday, I took it all back apart and removed the pump & filter... straightened out & trued the flange with some very careful tapping / bending. Put it all back together again with a new o-ring, sealed it up (flange fit much, much better this time), and poured in 2 gallons to see if it would hold for a few hours.. and it did. Good to go. Wired up switched power for my accessory lights and also got those mounted.
I took a 2 hour / 80 or so mile test ride around the block to make sure everything was good to go. No leaks, no problems - just a fantastic evening of riding.
I won't say it is done... but I'm thinking it is mostly there at this point. Finally. Put way too many hours into this thing over the last month. (Although, the Continuum of Broken Shit is still in place... the front turn signal stalk had dry rotted and finally fell apart on the ride yesterday

Of course.)
Time to get the bags mounted and take a trip.