Just get an older F350 single wheel rear axle, 7.3 powerstroke from 96-02.
I just picked up my F350 for 10k. There are a lot cheaper out there. Mines crew cap, hidden goose neck, new tranny (after 360K !!!), long box, linered, fully loaded. You can get a regular cab, normal f350 in those years for 6-9k.
In my experience (logger, siesmic worker, rig worker, etc etc)
Nothing stands up to the Fords in the bush.
In my seismic days we destroyed dodges to no end. The only chev was the pavement princess fuel truck, and the boses cadilac highway rigs. Veritas quite buying dodge because the of the 15 or so they bought, very few made it back to calgary with the suspension attached.
The older Ford powerstrokes are of proven strength and reliability.
No other truck of that day came with diffs it did. Leaf sprung (simple) front and rear.
Front Dana 60 hp, manual hubs, manual t-case. No pushbutton electronic t-case or automatic hubs to fail on you at the wrong times. Rear is a simple sterling 10.25 full floater.
The Ford is the lighter of the big three deisels in those day. The Dodges sink because of cummings weight, and the chevs because of suspension.
If you are truly going to hitting the cutlines, as hard or harder then seismic hands, then Fords are your realistic choice.
Just take a look at the few the 100 plus seismic yards around town and see what they are running. Or ask what they always ran in the years you are looking at as some have moved to dodges, but they are still a front end sinking tank in the bush.
At least ford nothing. Im not a ford man, i wouldnt spit on most ford cars if they were on fire. But they know how to make a simple, strong, reliable, and affordable work truck.
Ever drive in BC much? Ever notice what 90% of the trucks are? Yep, Ford. Cause they work in the bush. Whether you hate ford or not, thats just how it is.
Not to mention, buying an old f350 is cheap enough for you to keep your cj for when you come home and want to wheel.
good luck