tranny output shaft questions / request for used part in ATL

[shifty]

I'm in a dilemma. I wanted to have my driveshaft fabbed today and didn't even think to get a new output shaft for my T56.

After talking to j and slow in chat last night, they mentioned the TH350 and 700R4 output shaft should be about the same as a T56 output shaft - guys at the tranny shop say I'm full of crap, the 700R4 and TH350 are totally different and the guys typically don't deal with the T56.

Two things:

1) Anyone know if the 700R4 and T56 share the same output shaft as far as splines and size go?

2) Does anyone here around here in ATL have a 700R4 output shaft? I can think of one board member I might ask nearby, but curious to see if anyone else around here definitely has one before I ask.

Thanks, as always all I have left on the truck to finish is driveshaft, fuel delivery, install the harness and PCM and the hydraulic clutch linkage!!