bracket for dash speaker

[L48]

While disassembling the dash on my 75, I noticed the speaker opening on the driver side is different than the passenger side. The pass. side has a bracket with the number 3966575 cast into it. This bracket is held to the bottom of the dash by three screws and apparently the speaker is attached to the bracket.

This bracket is missing on the driver side.

Does anyone know for sure if this is an OEM bracket? If so is the part number on the driver side different than the passenger side?

(BTW I found the original build sheet in the dash between the tach and speedo!)

Thanks

 

[huk_finn]

(BTW I found the original build sheet in the dash between the tach and speedo!)

Thanks

Lucky find,,,,go play the lotto!!!! Bout the bracket I donno