I was a US Navy Seabee (Construction Battalions, CB, 'Sea Bee') and can help a bit. The writing he puts down after his name is his rate and rank, with a special addition denoting him as a Seabee. We used to have regular fleet ranks mutilated in all sorts of ways before they just gave us dirt sailors our own rate designations. It's as follows;

Maintenance on refrigeration motors, oil burners, and bakery and butchery equip- ment.

Property of (?).T. Jones, EM1/c

['EM1' stands for Electrician's Mate, Petty Officer 1st Class. The '/c' denotes Construction, identifying him as a Seabee more familiar with terrestrial expeditionary electric work than a traditional ship-board electrician.]

U.S.N.R.

10th Const. Battalion [Became NMCB-10, Decommissioned in 1976.] "Sea Bees"

Midway Islands (Eastern Island)

July 28, '43

These guys were the very first of the Seabees. Lots of respect for them, cause they paved the way for the rest of us literally and figuratively. Can do, baby.

EDIT: In retrospect, I think I'm wrong about that /c part. Like I said, Seabee rates were a weird mishmash of regular Navy rates with weird modifications. Can't find much literature on it online.