Found this in the barn today

[UNBROKEN]

Was going through my Dad's old tools....assuming this came from my great grandfather who owned a Ford dealership/repair facility in the 20's and 30's
It's a 5/8 drive ratchet, 18" long.
Also found some adaptors, extensions and sockets but haven't cleaned them up enough to see if they're Snap On also.

Any idea on rarity, value, etc?
Also how to clean it up without ruining it so I can get a display case for the shop for it.

PS...a quick shot of WD40 and it works as good as new. LOL

[snapmom]

Use a fine wire wheel, then some fine steel wool, then coat it with light oil and wipe it down. The socket does not look like a snap on. value of the rat 25-75. They are not hard to find.