The 572 will work just fine. I thought I answered that in another thread already. But, unless you just want to throw money away, a turbo diesel would probably be a better choice. Wait, what are you planning to use the truck for?
Daily driver, trails, parades, trailer pulling, think of anything non extreme here all would be best with a diesel, overdrive transmission and Michelin tires.
Truck pulls, mud bogs and rock climbing are a few things the 572 would be better at.
I have a 396 big Block in mine, NV4500 transmission and Michelin XZL 11.00-16 tires on it. I daily drive it to work, drive trails, tow trailers and put it in parades. 10 mpg towing other M715's and about 12 without the trailer. Since I still have the NP200 t-case, I am limited to 54 mph so all milage figures are at that speed. Guys that have put in 4Bt's, 6.2's, 6.5's adn 6BT engines don't have to worry about off angle climbs like I do and they get 18-35 mpg on the highway depending on the set up.
It is your truck, so do what you want with it. I just hate to see that $14,000 engine put in something that will never really use all those horses.