I believe the 45 is a Melling part number. The lock washers really don't matter- - - -I'd choose to leave them off altogether, clean the bolt and pump housing threads thoroughly with carb cleaner, and use blue Loctite on them. As long as the end plate doesn't get loose and fall off, the way the bolts are retained doesn't matter.

I used to cross-drill the bolt heads on the race car oil pump cover bolts and safety wire them, jut to protect that $15K engine so the driver could over-rev it and scatter it like a hand grenade!
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!