That's all I can do on this one too is just make guesses - rather not, but
howza-bout Mr. Isky?
EDIT; Sorry, somone else allready tried Isky.
Just for the helluvitt, here's a 'Vair powered Ultravan from '68.
Inspired from our mystery cam making Corvair powered Spartan owner? (The Spartan-air?
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)
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