The A/C in my truck stopped working last year, and this year I intend to fix it. I believe the problem is with the compressor clutch because it was making noise as it would engage or disengage. It was making this noise for a good year or so, and then one day the noise stopped and I have no A/C. So I am only `assuming` its the clutch. A new one at NAPA is $180. Has anyone tried changing these?