rear ac

recently bought 96 yukon 4wd 350 it has no rear air how hard would it be to put it in

I'm working on mine now...My rear ac is blowing warm and the front blowing cold. (You can check the thread if you're curious or can help me out.) The rear unit on the 2002 has both a heater core and an evaporator. The ac plumbing appears to tee both high and low pressure lines under the hood, then back to the rear evaporator. Wiring a blower will also be needed, and the rear blower dumps air through the ceiling ducts to the back seats. Probably not answering your question directly, but just giving you some additional info.