Not sure about the 49 but look under the dash at the area where the mirror should mount. There should be a reinforcement piece of metal there with holes in it to match the placement of the mirror. My 52 has them so perhaps yours does too.

It should look something like this...disregard the hole for the antenna which the PO had on the passenger side. Hope this helps.

http://i140.photobucket.com/albums/r19/LutherParris/52Panel/100_1398.jpg


1937 Chevy Pickup
In the Gallery
1952 Chevy Panel
In the Gallery
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1950 Chevy Coupe
Pictures!

I'd rather walk and carry a Chevy hub cap than ride in a Ferd.
I can explain it to you, but I can't understand it for you smile