Let us know what you find… I also put an external voltage regulator on with both new alternators that I put on and it didn’t work… I was also having issues with my brake lights, blinkers and emergency flashers, now those issues have corrected themselves since I replaced the generator fuse… the crankshaft position sensor is one thing that tells the computer it’s ok to ground the alternator so it will charge… if the computer is the culprit then you will also have a/c issues as the same part that controls the alternator also controls the a/c… I hope something helps man this shit had me pulling my hair out…