Quoting the Steele catalogue: "70-0331-73 1939-55 Weatherstrip, door edge, superior quality sponge. Similar to number 70-0145-73 but shallower. Please measure doors for required length. Many models.
70-0145-73 1947-55 Weatherstrip, door edge. High quality, fine textured sponge. Exact original configuration for ''47 to '55 (1st Ser.) and good replacement for earlier models. Easily follows contours. Please measure doors for required length."
These are both listed under Chevy trucks in the 2003 catalog. I don't suppose that it has changed much since then. So, the earlier 39-50 would have been used on 39-47 (1st Ser.) trucks and 48-50 "many models". The 47-55 would have been used on AD truck models as I interpret the catalog. But the fact remains that on my particular 52 GMC doors, I seem to have a lot of excess rubber.
1946 Chevy pickup, 1948 Chevy suburban, 1950 Chevy pickup, 1952 GMC pickup, 1957 Chevy pickup, 1939 Chevy pickup
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