Dodge did indeed use the same harnesses on most trucks, with some minor differences. According to the 01 manual though, the a/c connector is black.... two wire, dark blue with black trace, and black with white trace. If you follow the wires back, should be two more connectors on it for the hi and lo pressure switches as well.

 

I added ac to my 95 3500. It was very easy the only thing I had to change was the selector assy. The rest was simple add on

 

i live in washington state so in the summer it works good here cause its maybe like 89 tops during the summer lol

 

But he's got a 2000 not an 01

 

Been doing some more research and in fact almost everything is the same under the dash. The only thing I need to modify in there is a recirc door and pop in an evaporator. Might even leave the recirc door alone, need to see what that involves. It looks like Dodge just used the same parts for all trucks since only a small # of trucks were optioned without A/C here in the states and it was easier just to put in what they had. I'm going to start piecing together parts and go for it. So if anyone has any parts, let me know what you got and how much shipped to 06831. Most expensive thing is going to be the compressor and that should be 50-75 used, max. Going to document the process and to a DIY writeup..