It appears to be the original windshield washer pump with the housing removed. Here's a link to a replacement unit:

http://www.classicparts.com/1964-72-Windshield-Washer-Pump-Assembly/productinfo/67-825/


1960 GMC 1/2-Ton Pickup Truck
In the Gallery
Updates in the DITY Gallery
Now cruising in the Passing Lane