Well, here is the last chapter....
I ordered one flex disc from Pelican Parts in CA, and the other from Above All Motorwerks in IL. 2nd day air so I could finish faster.....
What do you know. The boxes came from the SAME warehouse!!! (the Pelican box has some extra tape on it)
Same invoices

Difference is customer support, I called above all, and get a recording saying they are at the racetrack, Pelican sends you an email every step of the way....
Above All was cheaper, adn I only used them cuz Pelican did not have the front flex disc in stock (whatever that means, since Above all sent me one from the same place).
Anyway, I ordered a front and rear flex disc (guibo, or Universal Joint) and 3 exhaust manifold bolts.
The flex discs are the exact OE and you can see where they actually used a grinder to grind off the BMW logo so they can sell it as aftermarket. (FEBI brand)
BMW part number sanded off
Getting everything back together, and broke the new exhaust bolt again.....too excited I guess.
New flex disc in place
Exhaust back in place
Shields too, oxygen sensors and wiring carefully put back...
Transfer case in place
Front shaft lined up same as it was removed
They instruct you not to run without the stiffener plate, since the bolts that hold it in place also hold down the stabilizer bar.
Sensor wiring put back
Damn you....
I see the replacement bolts are not exactly a match to the BMW bolts, since the grip splines go all the way down the wide part of the shank, not like the factory one on the right.
Ready to fill transfer case with ATF/
Filled it with less than one quarts worth of pumping before fluid was running out of the top hole.
Tightened fill plug, and lowered SAV.
Started her up for the first time in over 1 week (yeah, I work slow)
Took it for a spin. (it's raining).
I punched it from a standing start many times, and no noise while I give myself whiplash....
Problem seems to be solved....I'm HAPPY!!!