Yes, but no!

I meant, they are not a straight interchange. Of course shaft assembly ( complete up to the steering box ), collars, etc... will fit. Everything is the same size and lenght BUT, the bracket/plate to the firewall and related parts are totally diff ( hence also the firewall provision ). As far I recall the bracket/plate of 74s ( and I guess laters too ) is taken from A bodies. So could you fit a 73 column into a 74 or backwards? I guess yes if you have the correct bracket/plate assembly to the receiver and "build it".

My only doubt could be the lower bearing system. I don't even recall how is my 74 LOL, so I can't think if could get some parts unable to be matched.

Being 73s a problem due the "hockey puck" rag joint, I guess you could build a 74 steering assembly into a 73 mixing the required parts for it.

On 74 the bracket to dash frame also change from 3 attaching points from earliers to 2 attaching points, but that's not a big deal really.

However I could understand some 73 owner trying to install a 74 column on his car to save the rag joint problem for 73s, but never backwards. It would be a step back if you ask me.

I GUESS, you are trying to change from column shifter to floor shifter?