Thanks for all your kind words! What started out as a "hmm... it wouldnt be that hard to..." joking discussion with some friends over a couple beers has kinda taken on a life of its own.
Got some more time to stew over it last night & mock up where the fuel pump, filter, FPR, & fittings on the fuel tank will go. The best place for the pump seems to be laying flat on the back of the transmission, right next to the mount to the frame's spine so I can use that bolt for mounting. This also puts it as the lowest point, so it should have no problem priming/re-priming when I inevitably try to start the bike with the fuel valve off.
Speaking of the fuel valve, it will be in the same location as that picture, but I need to cut off the stock fitting since it's very stripped, and weld on a new NPT bung. The FPR can barely be seen in this next picture - it is way up under the tank (removed in the pic) near the top of the head, so that a continuous uphill run from the injector rails can be made. The little brass fitting in the middle, about 1/3 from the top is the inlet port from the fuel pump, and the high-pressure outlet to the rails is pointing backwards (out of view). The low-pressure outlet to the tank is pointing backwards too, a little higher up.
That position for the FPR should work out, and can be easily mounted to the two center studs at the back of the head holding the cam cover on. Since I'm welding on the tank already, I'll be adding another bung for the fuel return. Im considering putting it on the other side of the tank, but that would force all the fuel that gets returned to flow through the cross-over hose, which may be a restriction when the tank gets low. Plus, I couldn't get a tube inside up to the top of the tank, so it may have to go further forward, requiring tubing to be run forwards over the top of the head & next to the plug wires & coils. I'll need to puzzle on it a bit more before coming to a solution.
All tucked in for the night!