Instead of maybe donating a finger to the project, may I humbly suggest using an inspection mirror and a bright flashlight to inspect that pump lobe? There's a way to rig a dummy pump with the guts removed and flow gas through it on the way to the carburetor to eliminate the possibility of oil contamination, and use an oil pressure sensing switch to turn the pump off in case the engine stalls.
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!