Engine Identification / Please Help!

I have a Japanese spec TII motor. I need to find out whether or not it is a series 4 or 5. Plain and simple. The place the shop manual and haynes manual says to look reveals no identification. What parts are different between the series that would help me identify? I know I could dig in and look at the turbo wastegate but was just seeing if I could save the time and effort if someone has any ideas. I appreciate the help.

-Kai

Look for the knock sensor holes above the spark plugs. No holes? S4 motor.

Look at the TPS. Is it a dual or single? Single TPS is S4. Dual TPS is S5.

Electric OMP or Mechanical OMP? Mech is S4 and Elec is S5. I think those are the easiest looks.

I'd say the OMP is the easist/fastest way to check it, but all of the above will work