where should I put my oil temp sensor, pan?

Pan

Debatable, some people like to know the temp of the oil in the pan. While others would like to know the temp of the oil being delivered to the bearings after the cooler. A simple toggle switch and 2 senders and you can toggle between both.

This is really the only way to know what's going on inside the motor.

That's a good idea. I have mine in the remote oil filter housing which should be the same as the pan temp, I will have to see about installing one in the circuit after the oil cooler.

have mine in filter mount, works fine

What should oil temp/ water temp be ??

Good idea.

don't forget to run a ground back to the block from filter mount or gauge may not read, 210 is where I run now with thermostat

215 to 220 warm enough to boil off condensation .. t stats so i rarely see much water temp .. good oil thermastat to ensure good oil temps is key i was told by pfaff engines ..