Thank you. You are Mac Daddy. Just got it today and fits great. Actually better than the OEM one. I bought a new shifter ribbed cover and it actually doesn't have the little nub on it that the OEM one had that locked the socket in place. But this one is really tight and stays in place.
Fan (OEM) of fans (aftermarket)? For high speed operation put your AC on, that should kick hi speed on. There is an easy way to check low speed, I don't know it.
What RMI-25 does is basically clean out the crap in your system. It does have to cycle for a little though. Here is the link...
Is your fan(s) kicking on?
Get one of those infrared thermometers and check top and bottom of radiator.
Put some RMI 25 in there and then flush the system.
Lastly replace thermostat.
That's what I would do.