Thanks for the info, Mike

The four other 1954 Suburban locks/keys match each other (side doors, ignition, and glove box door).

The rear door lock does not match those keys.
That is the lock that I cannot find a key for.

It would be a big pain in the a** (arm) to try to reach up to the key housing/socket hold-on-clip (from the opening in the rear-bottom of the Suburan's panel-truck type door).

If I could easily reach the socket/housing, I could unclip/release the socket/housing and I would then be able to find the key code on the housing and/or I could replace that lock/housing with a new key/socket/housing that I have already obtained.

Do you know a friendly GM dealer that might have a set of try-out keys that I could rent?

Thanks,
Tim