You may have said it earlier in the thread, but, question for you concerning the fans.
As I understand, you are running dual fans. Now, are the electric or belt driven? If belt driven, is there a clutch driver that trips based on temp?
I ask because I have experienced problems with thermo-clutch driven fans and not a big fan.
Full electric driven do have their ideiocrancies to adjust driving habits.
Yep. The Ford Contour dual electric fan/shroud assembly with the last version Spal fan controller (before they discontinued it). I've been running this setup for close to 10 years now. Originally with the original 3.0L, and then with the 3.5L transplant.
I never had a problem with the 3.0L irrespective of what I was doing with the vehicle. 100F+ temps in UT, Lo-Lo-Lowhatever, mountain passes in 90F, 1000 lbs of gear and people - nothing ever made a difference in operating temperatures. I did not, in fact, ever have a problem with the OEM mechanical fan under the same conditions.
There never were any 'idiosyncrasies' to adjust to with the Contour fans and Spal controller. What I DID have to learn was how to set up electric fans on a computer controlled vehicle. One with really picky ECM programming.

And it also took a bit to understand - with some help from Spal engineering - the theory behind their controller. Once I figured out that the old ECMs really don't like lots of up/down temperature fluctuation and that the Spal controller is supposed to be programed to emulate a mechanical fan's behavior, the cooling system doesn't behave any different than the mechanical system did.
Which is how it should work. There shouldn't be any 'idiosyncrasies'. If there are then there's an issue somewhere.
After I finish the '99 3.5L build, I'll go back to transplanting a A/T 3.5L ECM into this Sport. As much as I hate the thought of converting it to a A/T, that's the direction I'm heading. I can't get my M/Ts rebuilt reliably here in CO and I'm still having lifespan issues with the intermediate shaft between the transmission and doubler. If I switch over to the AW3 I can still use the NP231 stuff and then I won't have to figure out how to fake out the A/T ECM, I can just wire the OEM TCU in and call it a day. That'll permanently fix the excess timing problem.
Edward