If you live in a mild climate, you can get away without a fully functional heat valve as long as it is jammed up in the closed (warmed up) position.
The OP lives in Wisconsin. He needs a fully functional one 6 months of the year. (Only 2 seasons in Wisconsin. Winter and pothole repair season.)
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission