I am looking to change the thermostat in my 2016 Cummins QSB4.5 from 180 degree to 130.
I know they do not offer one so I need to look for an after market. Any Help?

 

Don't know of a 130 degree thermostat or why you would want one. I am only assuming you ment to say something a bit warmer like 190 or their abouts.

 

This is in a Custom Built tram that travels around a 1.5 mile paved loop at a slow speed. Usually at idle with the driver riding the brakes. I am having a problem with the heat building up Due to the slow RPM's not allowing the Hydraulic cooling fan to turn normally.
It's designed to increase the engine RPM when in park to spin the cooling fan and help cool down the temp. but the temp heats up to high for it to cool down in the short time it is parked. I have checked the radiator for blockage finding none. my thought is to get the Thermo to open sooner in hopes of keeping the temp down. I also thought of removing the Thermostat.

 

I don't beleive going with a cooler stat is going to help your situation. If your not staying cool right now how is changing your stat going to get you any cooler?

Sounds like you need to address your heat exchange, like with speeding up your hydraulic fan or you may not being moving enough coolant with your water pump at that slow speed.