first, let me thank everyone for all their help. some great advice and i used all of it to solve the issue.
specifically, i would like to thank bill for being a strong advocate and superior machinist and engineer.
and equally the cap'n for his great advice and donation of the part in question.
here's the deal:
i am going to run the car as-is, thanks to a sweet skid plate/mount setup fashioned by bill. it's a rock-solid piece made from 1/4" steel and it looks as cool as any scat or empi part around.
in november i'll drop the engine and send it back to the builder, who is going to break it down for a full inspection and replace the pickup over the winter on his dime, to be done before march 1. he's also agreed to fully back the engine for 50k miles (i'm responsible for getting it to him stripped to the longblock), signed on the dotted line.
that's about equal win-win and lose-lose agreement i think.
in looking at this issue, it's apparent now that the broken bolt is not the worst thing that could happen in these scenario's. from what i gather, it's usually the case that breaks and requires a full teardown and magnesium welding on the inside. i started thinking long-term and i honestly warmed up to the fix idea pretty well because if the bolt is broken, but the case is good (which it is), then not replacing the pickup means that the case will never crack where it would if i or someone else over-torqued that nut.
i also wanted to avoid a lot of pissing about it. i also think that no matter how right i think i am, i have to avoid karma-inducing conflicts like these!
so, lesson learned. and since i don't plan on ever selling the car without at least documentation of the issue, i think i can drive it for now and fix it later.
thanks again
paul