Not sure on E-bodies, but B-bodies differ in column length and the gearbox splined shaft size PS/MS. If that also applies to E-bodies, and I can't imagine it wouldn't, then IF you can swap the coupler you'll have to move the dash bracket about 1.5" and the steering wheel will be that much further away. I don't know if a PS shaft can be used in a MS column, but it would seem possible.
I have seen people break the nylon pins for the collapsible column and slide the inner shaft out. You still need the adapter, and I personally would weld the inner shaft to the outer because it is pretty close to slipping out of the tube IIRC.
My 2 cents worth.......use the adaptor!! Somehow that frigging with the steering shaft and stuff scares me. I'm in the process of changing over to manual steering on my Challenger....and everyone I've talked to about it used the adaptor....pricey...but correct.
Re: '70 a-body ps column to manual box? - 09/04/0901:10 AM
Agree with SuperWrench! Don't mess with the steering shaft, don't weld! I switched from power to manual on my '69 Road Runner and bought the adapter from Rick Ehrenberg. I think he's a member of this board. I've bought a bunch of Mopar parts from Rick. Very nice guy, very knowledgable about chassis and steering. With his adapter everything bolted together easily and works perfect. Jeff