Definitely invest in an accurate temp gauge that can tell you exactly where you are as opposed to the old C-H. They do become addictive though. Sounds like you have the right gear and I agree with the 180 thermostat. Start with that and see how you go.
In saying that though if you have the cash and want to make sure no matter what then by all means go the 24" and be done with it. I doubt you will be having this conversation again if you do.
"The simple answer is, even if I have decided I still don't know what to do."
Fans are controlled via a variable thermostat with the probe placed through radiator fins. Probe is in a dielectric paste to make a thermal connection between fins and probe. Decent temp gauge will help set fan at desired temperature.
The logos and trademarks used on this site are the property of their respective owners.
We are not responsible for comments, advice, opinions, products or services posted by our members, as they are the property of the poster.