Thrmostat. I just did a coolant refill and drain and chgd the thermostat and I believe the new one was a 195 ? I this too high or would a 185 be too low ? Now im concerned about this UIM problem, mine appears to be a 2001 looking at the date codes on the manifold, were these changed or the same exact ones as the orignal ?

they are the same as all the earlier series 2 3.8'*.
The series 1 3.8'* had an aluminum intake as do the series3.

195 degree thermostat is stock for the L36, so you're okay. If you were planning on doing modifications or running the car in extremely hot climates I would recommend a 180 degree thermo, but as of right now you've got exactly what the car came with from the factory. No worries.