need some 1961 gmc 4x4 knowledge

[samfaucette]

better pictures coming but i need some help. i bought a 1961 gmc 1/2 ton 4x4 3 on the tree and the 305 v6 all original was bought new in my home town. my question is what do i have, i know about 67-72 but this is my first 60-66. i think its rare it has a big back window chrome grill and trim aroun back of cab (i have all trim not pictured and the back bumper) it has rust in the typical areas mounts rockers corners etc. the rest of the body and floor is solid surface rust only (except for the driver lower fender) it runs great and i can drive it any where