Power Loss

Okay, I've asked this before, but the problem is getting worse. My headlights and interior dash lights are dimming WAY more than they should when I hit the brakes. I understand that lights dim, but not like this. Battery is brand new, alternator is pulling 14.3(iirc). Is there a way I can test my compressor or a/c clutch to see if that is the problem. Also, someone had mentioned before about the ground for the headlights and it being on the inner fender? Where?

Thanks again.