If in doubt test the TPS as per 5-18 to 5-21 of service manual.
I believe there is a small setup angle/voltage and that is why they do not sell them separate.
I believe the aftermarket fuel controllers can be used to test/set TPS.
2005 1300c Red, Mustang seat, HK 2.5 straights. Leds for safety-front & back. 178,645 miles of smiles