'37 doesn't have defrosters but if the '40 dash is as easy to remove, it may be easiest to install or fabricate the defroster vents than reaching under there. I like others have read that you pull the dash to get to the nuts.
Larry
Old man᠁Old truck᠁neither one goes very fast. All you need in life is TIME, PATIENCE and MONEY.
If you are missing one component, you'll need an abundance of the others two.
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