Just did a TPS test this morning - 0.07-0.1v with throttle closed, 4.60-4.65v wide open.

Going to have a good check over every sensor and make everything is tight and connected up correctly.

Can't see much more that could be at fault. Only other thing left to do is spray carb cleaner or something similar around the intake to see if it could be an air leak; I have my doubts since every gasket and seal on the intake and exhaust side was replaced when I built up the engine.