slapstick shifter doesn't fit ?? has ball shifter now..

OK guys....the guy doing work on my Challenger tried to put the T-handle slapstick shifter on and he says it wont fit .....problem: the shaft is a round one and t-handle has a squareish hole and he said it won't fit . It has the ball shifter on it now.....Question: where can I get a different shaft part that the T-handle will fit OR how do I make the T-handle fit??
I saw some instructions on an Ebay listing but can't read the whole thing....anybody have the instructions
Pics attached of what I need??

another pic

You seem to have the 70 style shifter. For the T-Handle you need a different mechanism from a later model. Fortunately they are not hard to find.

Here is one from an ebay ad (not mine) for $50 at the moment. You can see the difference in the shape of the shaft.

Thanks....all I need now is someone who wants to trade .......lol

Do you have the rest of the parts for the ball type shifter? I know there is the ball, button, and I am assuming a chrome dress up shaft to go over the bare steel parts there. Also I believe the plastic slider in the gear selector indicator is cut different for the round shaft.

Might be willing to trade since I am not about originality in my car, and I hate my factory T handle.

here is the best pic of mine I can find.....my actual car......

I need a 70 style and have a 71-74 for you. Lets trade get in touch with me. I need the ball, the chrome piece, and the bezel also. I'd even throw in a couple of bucks with the deal as I was about to buy one.

I sent you a PM.