The interior mounted rear-view mirror was not optional, but standard equipment on the 1960-1966 Chevy light-duty trucks, according to Chevrolet Pickup Color History book, published in 1994 by MBI Publishing Company and available from
www.motorbooks.com. The rear-view mirrors that became standard equipment in 1966, were the exterior, door-mounted rear-view mirrors.
The factory interior rear-view mirror is centered left-to-right and the first two holes are 3/4" above the windshield grommet and the top hole is 2-1/2" above the windshield grommet.
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