Jon, if you have access to a lathe, it would be very simple to bore that HEI housing for a lip seal on the shaft. That would absolutely prevent oil from migrating up into the pickup coil area. I'd also suggest installing a Torrington needle bearing below the seal while the housing is in the lathe.
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!
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