Now, on to the bureaucratic BS; Your new compressor warranty will require a couple things- that you flush the condenser, or if you have a parallel-flow condenser that you replace it. I always replace the accumulator and flush the evaporator, but since recently twisting off the evap fitting and replacing both I discovered that GM says specifically *not* to replace the accumulator unless it's damaged (probably to keep from ruining the evap fittigs) I'd start by removing the compressor pressure sender fitting and checking there and the hose manifold for metal debris. If there's obvious trash there, just replace everything you can including the accumulator *if it comes loose easily* and backflush the evaporator. You can flush the hoses, but they're pretty inexpensive. The condenser and orifice tube are not optional if you have a parallel flow condenser.