Old School vs Magnum on 86 Dodge W100

Team, I'm new to this forum - thanks for giving your time. I have a decision to make. My son (who is 17) is taking an old W100 4x4 I had sitting around and decided to revive it. It originally had a slant 6 but was converted to a 318 many years ago. That 318 is about dead. He purchased a running 94 5.2 magnum from a Dakota with the intentions of replacing the 318. He got all the electronics, wiring harness, and fuel system from the Dakota to help the conversion. Before installing, I recommended we tear the magnum down to inspect it. He did and it need a complete rebuilding. Block is fine, Cam is bad. Crank is fine. My question at this stage is whether to spend time/money rebuilding the old engine (which we have not torn down yet) or continue with the magnum? It seems to me the advantages of the magnum is fuel injection (and maybe one or two more) but the disadvantages are we have to do the electronics, wiring, & fuel conversion. If we stick with the old style, I feel we need a 4 barrel intake and carb (as opposed to the original 2 barrel it came with). That's a new intake and carb cost on top of a rebuild. And probably a newer distributor and ignition system. I would appreciate any thoughts for carbureted vs Magnum approach. Pretty soon, I'll be making decisions about machining, cam, pistons, etc so I could use the advise.