A bit of searching the GM# 602073 in GMPartswiki seems to indicate this mirror was offered for 1939-46 Trucks for use on an extendable mounting arm with a different mounting bracket (see screenshot below).

Would venture to say this was an option offered, most likely for Big Bolts or other vehicles that needed mirrors like this for better visibility. The description on the extendable arm (GM# 985407) says "12-1/8" ctr to ctr...extended 7 in".

So from what I could find, not correct for an AD era truck.

Dan
Attachments
Large round mirror and extendable arm info GMPartsWiki - Master Parts Price List July 1946.png (56.58 KB, 105 downloads)
Large round mirror and mount info
BLANK.jpg (227 Bytes, 105 downloads)


~ Dan
1951 Chevy 3 window 3100
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