I'd plumb a direct reading gauge to the oil pressure port and spin the oil pump with a 1/2" drill motor. No point in burning up a starter trying to get some oil pressure. The wiring looks right, BTW.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!