Chad has been on a square-body Chevy kick ever since he got ahold of his 1987 Chevy dually. Can’t blame the guy, the truck is sweet, but when it comes to brand favoritism, I have to lean towards Dodge for trucks. Look…any American-sourced pickup that was produced between the late 1960s and the mid-1990s is a golden score in my eyes, but here I have to stick with the Dodge D-series/Ram and my method of madness. So long as all the metal is in good order, you can run whatever you want, from a slant-six to a big-block to a Cummins diesel. They’re dirt simple and durable, and the running gear up through the end of 1993 is about as good as it gets…nothing fancy, just good. 
Finding a crew-cab Dodge isn’t easy, but this 1985 Ram W350 came about honestly: the government. The United States Air Force loved these trucks and bought them by the truckload. The 360 underhood isn’t a bad choice, but it isn’t going to wow anybody either, and that 727 automatic needs a GearVendors unit as soon as possible. Being a one-ton, which would you go for: a very stout 440 or just bite the bullet and get to work on swapping in a Cummins? That’s a tough call, but either way you’d win! 
eBay Link: 1985 Dodge Ram W350 Crew Cab
I’d sell the lift kit and wheel/tire combo to fund slamming it properly, and I’ve already got a 440 sitting in the garage….
Depending on your state’s smog rules, a big block swap may be out of the question because the engine was not offered in that model year. If you’re thinking diesel, the engine was not offered until 1989. And what, pray tell, is wrong with a 360? You plan on taking it to the track?
i agree with mopar or no car… being a one ton version its rolling on 4.56 gears, reasonably limiting its top end to high 60s (i currently own a one ton 85 4×4 with the granny geared np435 box) a healthy 360 will split the difference between cost and fuel economy (maybe a 408 stroker?), while retaining a semblance of legality… you WILL have decent off the line acceleration and along with a good overdrive unit, you might get highway mileage into the mid to high teens, doing the legal limit, while being unstoppable offroad (as long as it fits in your local trails)