I think I figured out that you can use the Cyclone TC single crank system in the TCX. I can't find info on exactly which parts you use from the 7508(pro4 servo saver set), but i have bits of it here and have ordered 2 more for my two tcxs, along with 75143s and 61321s. I think I'll be able to use bearings I have and I think the servo and remain where it's supposed to be! Any info on those things would be very awesome and gratefully received!!!
I measured it all up and just seems the ackerman will revert to that of a TC, so I just hope that feels ok as it felt fantastic with the original rack.
I will look at Ebay, I know I was looking before and the only ones I could see had buy it now prices of well over $120, thanks Chris, I will for sure check it out.