I had this situation once .this is what I did.
Changed the TPS to the new style variable type.
Made a small circuit up with two relays.its input is the analog from the new TPS too.
Made the two relays switch at max and minutes positions just like the old style tips would have.
Quantum Coupe with V04 on Ford 1.4CVH,Quantum 2+2 with Custom V04 on Jaguar 3.0l AJ30 V6
mini GPIO :done More soon
CANbus broadcast interface: done
Simple sd logger :done
External CAN io: Inputs :done
Gearbox controller: working