i have a 99 f350 and f450, both with the 7.3psd, both drw.. 350 is 4wd.. 450 has air bag suspension.
I ditched a gasser half ton for those for towing. 350 will do bumper or gn.. 450 will do bumper, gn/5thwhl. I have a 3/4 ton f250 with 6.0psd.. an 04.. but I prefer the 1 an 1.5 ton for towing. 450 has 4.88 rear.. 350 has 4.10 rear. 450 don't fly faster than 72 down the interstate.. but will drag a loaded 14k trailer slapping the road now and then behind it... 350 is right behind it.
both are auto.
upgrading from a 5.4 to a 7.3 you will wonder why you didn't do it sooner... I hope to never go back to a half ton or a gasser if I can help it..