Toyota Repair: A/C compressor, compressor clutch, metal particles

Question
On 95 Previa, when a/c is engaged, get a growling sound from compressor/bearing, I think. It is quiet when clutch not engaged. Is this the clutch bearing or is there an internal compressor bearing that could be going bad? How do I replace the offending bearing?

Answer
When there is noise only with the compressor clutch engaged it means there is an internal failure of the compressor, unless you can find an a/c repair shop that is willing to repair the compressor you are pretty much relegated to replacing the compressor with an exchange unit, at the dealer we do not repair compressors we replace them with remanufactured units, to be frank, it will probably cost a lot more to repair it( if even possible) than to replace it, most of the time the internal failure will destroy all of the moving parts inside, when this happens metal particles are spread throughout the system, fortunately if caught early the receiver dryer will trap most of the particles up to a point. replacing the compressor and receiver dryer fixes the problem in most cases.