Diesels?

We all know that the diesels that came in the bbs (box body style) were hunks of crap, but what if i were to get a truck like that and somehow put a newer diesel engine in it? What would all be involved in that? I know its got to be easier than starting with a gas powered truck.
I ask because im looking to buy a 40ft enclosed gooseneck and will be needing a lil more pulling power.

i wanted to do a 6.5 turbo swap in mine until i looked at all the wiring and whatnot.......I did a fuel injected small block swap in mine....hasnt hurt my performance and I get double the gas mileage!

Hows it pull? Mileage? How much are you pulling?

The most I pull is a single car trailer. As far as power, pulling or regular driving, it is about the same as the 454 that was in it. I actually like the small block better because it is computerized so I could also used a computer operated tranny. The advantage comes with the 4L80E tranny that I have in it. That would be the same tranny that came in the newer model duallys, even the diesels. As far as mileage, I get 17mpg highway empty, and 12mpg highway hauling.

So im looking more and more into a diesel swap, but instead of dropping it in the 86 Im looking for one to put into the 68 when i build it. Now all i have for it right now is a 3:83 rearend and the only time i plan on towing with it will be down the highway to various shows (never in town)
So which one of the big 3 manufacturers would you reccomend? I figure i want to build everything to handle a loaded 40' gooseneck.

i would almost say go with a newer duramax and allison nuihtn but rave reviews from whati have seen

Arent the duramaxs' the quieter sounding ones?

stock but sound nice with some upgrades

they are way too quiet for a diesel! I found out the 6.5 turbo isnt a hard swap. Im gonna be looking for me one.

Which one is the 6.5? And also is there any notable size difference between them? Remember i gotta try and shoehorn this thing under a 68 chevy.