[6pack] prop shaft removal

[dave]

?hi, all.

getting some serious vibration that stops as soon as I remove my foot from 
the accelerator.

thinking it might be the prop shaft.

I want to ask this before I start:

the exhaust header is attached correctly; unfortunately an overzealous 
muffler guy welded the rest of the system together (in other words, the 
joint between the exhaust and the header is fitted; the rest of the joints 
behind that are welded).  it's a 72 with the 2 pipe system.

does the exhaust have to be removed to remove the prop shaft?