Ive yet to have a problem with my stuff I got for my '96 from Auto Zone, But it was a Reman Delco compressor, which is noticeably loud when it kicks on, and the aftermarket dryer and aftermarket condenser. I had to go GM Parts Dept to get the line between the Condenser and Cab The GM price was $20 and change, Cheap. Not the one from dryer to compressor to condenser. Id say get the Delco comp hes talking about, aftermarket dryer, GM line and aftermarket rest to get what ya need at decent price/quality ratio. You just need a set of gauges, a vacuum pump and necessary Freon and the pour in oil and pour in dye. Do get the dye. It will help you later IF you need to find a leak. I'm pretty sure its like 2-2.5 cans of freon for anything but a crew cab, and 3 cans if its a crew. If it is prior to 1996 then you'll need to get the "retrofit" adapters or take your lines to a shop that can weld on the new fittings to your aluminum lines. I would rather have the welded on as opposed to the adapters simply due to the fact of having two less leak points.
Little tip, Let the vacuum run for close to a half hour to make sure there is no air or moisture in the lines which can degrade performance.
You'll need to jumper the wires that go to the switch on the dryer to get the compressor to kick on for about a can and a half to two cans, then you can run it with the switch til you get the rest in.
