If you're hauling off the bumper the weight is more of an issue than if you use a 5th wheel. 5th wheel offers a MUCh better load capacity there as well as towing stability and overal vehicle control.

Brakes are the real killer there & it'll depend on the rig you get as to how much of a PITA it is to upgrade. More recent models are easier to upgrade, but then if you really wanna do it right swap in newer axles & springs that are rated for a higher weight with modern brakes already installed.

My old bolt of choice is the mid 60's Chevy 3/4 ton, anything before '69 when they started to lose those flowing lines. The Apache is a beutiful truck. They are tanks in stock rig, & the one I used to have was a mean ol' '65 with a 327 with TBI and custom exhaust, TH400, and 5.31 rear. Pulled weight like nothin, cruised at 70 with ease, and wes a joy to drive. I'd love to have a 3/4 or 1 ton flat bed now!

1956 GMC 370 dump " 'Tater "
1970 VW Volksrod "the Black Bomber"
2007 Chevy Avalanche
2020 Jeep Cherokee Trailhawk,
2005 Harley Davidson FLHTCUI

I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things.
But thats just MY opinion! :P