I understand and appreciate all of the above views and reasoning on this topic from you guys. Here's another farmer John (whoever he was) idea.
Cut one of the radiator hoses in two and install a ball valve so you can close down flow till it warms up to 3 bars then open it up some to get temps you want ?????? The fan switch and fill cap are still in the picture then. I know not cell phone techy enough but satisfyingly simple like a patatoe.
rj