Honestly I'm not a 318 fan unless it is a Magnum. They run for a long time but they really don't set the world on fire.
My son swapped out the 125HP 318 out of his 88 Shortbox 4X4 for a Magnum 360 and it was like night and day. The 360 Magnum is a pretty stout package for 93 technology, they get decent power and pretty good fuel economy. The stock intake/injection setup is the one thing that holds them back.
Back in 1974 I would venture to say the 4 bbl 360 was the best all around smallblock available from any manufacturer. Lots of big blocks got their tailpipes handed to them by a 4 bbl 360. Remember the SS454 Chevy pickup truck that was slower than the Lil Red 360's?
I bought a new 318 magnum in my 92 pickup and that thing hauled butt, So I made the mistake of getting another 318 Magnum in my new 96 pickup, that truck was a dogg, I always wished I had sprung for the 360 Maggy in the 96 and I would recommend only a 360 magnum for a swap. Sure the topend HP will be limited by the intake setup but you'll get more lowend grunt and you could run a bit higher rearend ratio to take advantage of the torque for better fuel mileage with the 360.

Sheldon