I bought this truck last income tax season, I really wanted a slightly older diesel (either ford or dodge, mid 90's model or so) but couldn't find any in my area without paying huge dealer prices.

What modifications would you suggest for more torque?

 

I have a 340 that has a Lunati cam, and 5 axis ported Indy cylinder heads and Keith Black pistons. I had it bored .030 and stroked (Scat crankshaft) to a 416 cid and it makes over 500 horsepower and 530 torque. I would imagine a 360 would easily make 390 horsepower for under $3,000.00,
FF

 

500HP+ and 530 ft.-lbs sounds like a beast!!

 

It does not have power steering or power brakes, though.
I would call a local engine builder and I was told by Ray Barton (raybartonracingengines) that any Chrylser engine benefits from stroking. He will be doing the 440 in my Coronet during the winter. You could just get a nice set of heads, exhaust headers, exhaust system and a cam to start with as these will be needed if you end of stroking the engine later,
FF

 

I agree If you're going into the engine porting and polishing you're heads would be wise. And you can do it yourself..Get a book or find out how online..Saves money..Headers , with a good exhaust-the right cam and intake, with 6.5-1,Roller rockers..Bore it .30 over, and use pop-up or flat top pistons. You'll be happy with it..
Summit sells good Kits for builds like this..