Friend of mine has a 72 GMC 1 ton with a 4-53T, a Spicer 3000 series 5 speed direct drive, soon to be swapped for a 3053A overdrive, and a Spicer 5831 Auxiliary transmission. It's was his daily driver until recently, and he has driven it all over the country, and still does.
He swapped for a solid front axle, made from a 4wd axle, but just a pipe for the center. the cab needed no work to fit the engine.
Another friend has a 4-53T, with Spicer 12 speed in a 70's 3/4 ton Dodge truck, it's his daily driver.
I had a 73 Chevy 1 ton with a 4-53T, a Clark direct drive 5 speed, and 4.56 gears, needed better than 3.54 to be right. It had the independent front suspension with lots of modifications to it and the oil pan. I sold it, as I felt I could do a better job on a conversion. The new owner promptly installed a ford 9" with 2.?? gears, and drives it everyday.
I just recently had a 61 ford f350 with a 6V53T, and a Roadranger 10 speed overdrive. Drove it home to CA from VA with 4.56 gears and 28" tires, swapped axles for 3.73 and 38" tires. Then drove it from VA to CO to WA to NY and back to VA, it was a great truck for road trips. I feel that a 6V53, while it did fit nicely in the Ford, is to big and heavy to be a good swap in a 1 ton size truck.
My own project, a 48 Chevy 6400 has a 4-53T, Roadranger RTO-6610 (10 speed over) Dana 70HD with 3.54 gears, and will have 9R22.5 tires at 38" tall. This truck I plan to keep forever, and it will be my daily driver.
the engine, transmission and axles are installed and done, next comes all the plumbing of brakes, fuel, and air (for the air starter). The fit the cab with some sheet metal work, and finally restore the sheet metal and apply paint.
For your truck, what size is it, or will it be, what will you haul with it, and how often?
If you want a small truck with good mileage then a 1/2 ton with a 3-53T would be best. I have another friend with one of those, he loves it, daily driver again.
For a more useful truck a 4-53T is best, and I feel that a 1 ton is the minimum you should start with, although 3/4 would work depending on your use.
there are some nice Spicer and Fuller 6 and 7 speed transmissions from medium duty trucks that you may want to look in to. If not that then the NV4500 would be a good choice. For a work truck a 5 speed with evenly spaced gears is a good start, but I really liked the 10 speed in the Ford I had, and I am sure to like the one in my truck, I always had the right gear for the conditions, where with a 5 speed you often need more in between..
There are 53 series Jake brakes available, they are extremely expensive new, and quite expensive used if you can find them. I have a set installed on my 48 Chevy. I don't think an exhaust brake is a good idea on a Detroit.
Before you ask, 71 and 92 series are way to big for anything less than a 2 ton truck, but that's not to say it has not been done..
Grigg