Question about voltage limiter

RTE instructions say it isn't needed but use it anyhow( possibly because of a tight fit it did seem a bit loose)
After installing the new limiter it seems to be running 25% low I let it run about 20 minutes and the temp barely moved going to fill the tank tomorrow and see what the gas gauge reads, if it's still off I'll just go back in and check all the wiring and grounds..... Again. The wiring is a mess on this car, I think I'll eventually have to break down and get a new harness, under hood isn't much better

Hey Steve 225, what is the process on removing the instrument cluster? I want to clean mine up and install the IVR4!