just a quick wrap-up, the SRAM cranks work OK on the 123mm JSS spindle. A little too far out, Center ring is at 50mm instead of 47.5, but the FD derailuer works now on all 3 positions and rings, neither stop-screw is bottomed out or backed out completely. I will get the 118mm BB spindle at some point down the road.
The SRAM manual for these cranks is correct under the square-taper section, bottom right corner of diagram. Calling for a 113mm spindle with 2.5mm spacer on drive side. Equivalent to 118 mm overall length. Hooray for SRAM
https://www.sram.com/sites/default/f...nksets_web.pdf

Now to just get the rear hanger re-aligned