Looks like a good project. Welcome to Stovebolt! Check out the Big Bolt forum for more info on your truck.
Those screws are called clutch head screws. Bits and screwdrivers for those are available. Do a search of the forums for more info. These have been discussed here before.


Rich
1947 Loadmaster
1947 Chev. Loadmaster
1959 Chev. Viking 40

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