If it is indeed the compressor that is your problem just unplug it. There should be a two wire plug that goes to the compressor, unplug it and zip tie it up out of harms way. Then your compressor can't engage even if you use any of the defrost settings.
If your compressor is the issue it would only make noise when you have the AC on or any setting that includes defrost. If your truck is making noise all the time it is one of the other accessories or the idler or tensioner pulley as stated above.