M20B25 thermostat question

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

Hi folks,
	The thermostat on my wife's M20B25 expired recently and I was
surprised that the old (factory?) one was installed with an arrow facing
towards the engine (back), not Up as both Bentley and dealership mechanics
recommend. So I installed the replacement thermostat with an arrow facing Up
and the engine runs at around 10 o'clock heating up to 12 o'clock in stop
and go TX traffic (100+F ambient temperature).
	Fast forward to last night. My M20B25 has started heating beyond 2
o'clock in TX autocross runs and troubleshooting lead me to replace my
thermostat. Imagine the surprise when my (factory?) thermostat was also
installed with an arrow pointing towards the engine.
	Thus the questions: 
 - are M20B25 thermostats really supposed to be installed with arrow
pointing up? 
 - is there any reason why the thermostats on two different M20B25 engines
would both be installed identically wrong?

TIA,
alex

------------------------------