His Clifford does not have heat.
I never had a heated intake on my Offy of Clifford & they worked fine IMO.
The damm header is right under the intake manifold & heats up the intake manifold pretty damm hot.
We are in So-Cal so it does not get that cold here.
His ride, a 67 Elky, & it's not a daily driver, for that duty, a Honda Civic.
What is the carb you have on the 65 Wagon? Model #?
MBHD