I've got a couple of engines with solid top valve covers and the oil filler on the road draft tube. Those draft tubes aren't all that scarce, so installing one would probably be an easy fix.
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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