You need to get busy with a voltmeter. That is the only thing that will answer these questions. Some key points to check with motor running, and a jumper wire so you can jumper the fan stat on and off for tests:
"What is voltage" with / and without fan running, with engine running "fast idle"
...........at starter relay stud
...........at bulkhead connector the "big black" socket (ammeter/ alternator}
...........at bulkhead connector the "big red" socket.(fuse link/ red to starter relay)
...........at alternator output stud
...........at the "key" side of the ballast resistor, or where that would be if not used, AKA the dark blue feed coming out of the bulkhead connector
Crackedback on here knows what he's doing as well
