If you installed three point seat belts, you’ll recognize the bigger center hole. The pop rivet gives it away! There is a threaded backing plate that is being held in place with that pop rivet until the seat belt in bolted in place.

I have no idea what the other two holes are for. Probably made before the seatbelts were installed.

EDIT: I like DES57’s guess, fire extinguisher mount, prior to the seatbelts!

Last edited by Phak1; 06/30/2021 1:08 PM.

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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