I just went though this process...
What type of racing are doing? Asphalt, or carpet?
If Asphalt and you are running 19T motor or Mod, I would recommend the ITF, but this is only if you are not able to get the traction you need from the FT kit. The ITF is for extra flex over the FT, which is need in low traction racing. The FT would work just fine for carpet.
You can purchase the FT upgrade kit and it will convert your RTR to a FT car. BUT…. If you are new and you are not racing, I would not recommend this… the FT kits from any manufacture are for racing and not hitting things… the insides will come out if you hit hard enough or enough times…. No amount of double sided tape will keep or protect your equipment in a double deck CF car… The version you have is a tub, and this is best for bashing and learning, as it protects the insides better.
If you go to the ITF, you first need the upgrade kit for the FT then you purchase the ITF upgrade, which should only be the 2 desks and center.
Hope this helps…