Brake questions from a newbie

[TKG Midwest]

Trying to put brakes on a '51 3100 (from scratch..nothing brake-wise on the truck when I bought it) and as I went to install the master cylinder (supplied by the seller), there are two brake-lines to hook up, one from the rear, on to the front brakes. Did I get the wrong master? Did a previous owner reroute brake lines or eliminate a "T"? Also, is there a clevis that screws onto the master cylinder rod? None of my cataloges have it listed, and the brake manual shows a "eccentric bolt"? any help on this is appreciated