The repop rubber parts of today leave much to be desired IMHO. The rubber basically crumbles apart after a short period of time sadly.

The original part is listed as GM# 3765360 and fits your application, as well as spanning all the way up into the 1990's on various truck models.

You can still order an original GM# 3765360 from GMPartsGiant.com. Currently listed as on sale for under $30 plus shipping. Don't be concerned about their vehicle application listing for "1985-90". It's the same part/part number used all the way back to 1960 (see Master Parts Book screenshot below).

Hope this helps. wink
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~ Dan
1951 Chevy 3 window 3100
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"My Grandpa Carl's Truck and How it Became Mine"
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