Ok but just bear in mind that one feature of a 'cold side' stat is an opening delay, and that can be bit of a game...
Before the stat can be fully opened there has to be enough heat in the bypass coolant (easy if you have a V8) to crack the stat and let some cooler coolant from the bottom of the rad creep past, and then only for it to be closed again as the temp within the stat housing drops. This open/close cycle looks to be repeated multiple times until the coolant in the rad is raised enough to hold the stat open. The delay will depend on a number of variables like the air speed through the rad, the ambient air temp, the rad efficiency and the longer the delay in opening, the hotter the engine gets.
The stat on my little 1.8 with its huge radiator poking out the bottom of the car would open normally if I let the engine warm up from idle with no air flow through the rad, however it was moving fast it was a different matter. The engine temp could rise dramatically as the hot bypass coolant from head struggled to get enough heat into the stat housing to open the stat, sometime it just wouldn't open.
Something to keep an eye on and perhaps come back to if you run out of other suggestion. Have fun
