Ford or Dodge

Any TSBs on a 13 year old truck would most likely be fixed by now and an 06 Ford chassis and everything else is as relaible as you can get, all things considered, Except for the engine. Since you don't know much about trucks, if you don't know much about trucks don't get a Ford 6.0 diesel. Any of them.
Ram will be a good choice, in general. Won't pull quite like your old Excursion, but as with any vehicle with that high of miles, the condtion of the truck is just as important as the brand.
All bets are off if it will have minor or major issues at 200k unless you have good assurance of the vehicle history.
Of those 2, I'd get the Ford because I'd want the power of a diesel, but at the expense of k owing the issues and it would have to be more of a deal tha other trucks and I'd plan on bulletproofing it.
For plug n play I'd get the newer ram. 7 years newer is more peace of mind that you won't have as many old vehicle problems as soon, but same due diligence is required with such high miles.

I'd go with the newer truck regardless of the brand.

Don't know what your price range is, but I would not be looking a a gasser with close to 200,000 miles.
Between the two listed I would take the Ram, if other conditions were equal as it is also seven years newer.
Personally I would be looking for something newer than a 2006.

Neither...
While I haven't driven the 5.7, I can only imagine the amount of suck that would be. My work truck is a V10 Ford and my fellow worker has the same with the 5.4 V8. Both are later model 5spd auto with 4.30 gears, and weigh about 9500. The smaller engine is ok for in town but horrible in the hills, add a little bit of elevation and it can't maintain speed where the V10 plenty of power to spare (and runs in a taller gear as well).

Having a family member that owned an '04 6.0L PSD, personally pulled the turbo twice of the three times because of a stuck unison ring, replaced the egr cooler out of fear, plus a few trips to the shop for minor things. They make good power, well built truck, but that engine's emissions system is a time bomb. $5k to bulletproof from what I remember.

I'd hold out for a 5.9L Cummins, another V10, 6.2L Ford, or 6.4L Ram.

I don't see a win in either of these. If your looking at trucks in this stage of their lives, than I assume you wouldn't be excited about paying thousands more in repair costs. That fact removes the FORD 6.0 from contention. Your odds would be better going to Vegas and putting your truck budget on the Roulette wheel and choosing red or black. I know you don't list GM, and I assume if getting something newer isn't an option or you would be doing it. If your looking at trucks with this kind of miles, do yourself a favor and consider the GM 6.0. There is not a more proven, bulletproof engine on the road today. There are many contractors here and everywhere that have more than 300K on them. Something to consider....or not.

Have you researched a 6.0 PowerStroke? Lots of info on that. There is a reason resale is so much lower than Chevy and Dodge.

Personally I’d keep on looking and try to find a way to I crease my budget. I don’t want someone else’s 150,000 + mile truck.

Agreed. None of the above.

I have a few family members that put well over 300k on 6.0L diesels. One was bullet proofed and the other tuned after the warranty was up. I would take a 6.0 between the those two especially since it is a 2006 and most of the issues with the 6.0L were resolved by then.

Thats dry weight on the TT. Probably 8500 lbs loaded up. 840 lbs dry hitch weight. 1,000 lbs loaded. You'll overload the 1500 instantly.
3/4 ton gas at a minimum.

Grit dog wrote:
....if you don't know much about trucks don't get a Ford 6.0 diesel.

Definitely. If all the bullet proofing is done, it could be a reliable engine. If not, you're buying a money pit. Unfortunately there is no good way to believe the seller if work was or wasn't done. Don't take this risk.