i did a quick look at the space needed above the input and output shafts for the T56 and the TKX, it seems the TKX would require significantly less tunnel work...but I'm just looking at pics on the internet so who knows really.
That's my understanding as well based off the installation instructions for a TKO in an A-body and that's basically the same size as the TKX. TKO only requires the tunnel to be sliced and "expanded" in a few areas while looking at @goldduster318 's build thread the T-56 requires pretty much an entirely new trans tunnel which looks to be at least a few inches taller than the factory tunnel. Expanding the factory tunnel sounds like a much easier job to me but idk.
I'm still up in the air about it, hoping someone else gives it a shot in an A-body. Realistically I won't be able to afford to do a 5- or 6-speed swap to my car for another couple years anyway. Hopefully my 904 holds up to at least one more season of track days.
