Truck 2500hd Silverado 6.0 or diesel, 6.6 or 8' bed ?

Recently purchased a 30" travel trailer gvwr 10000Lbs. Sold my 1500 1/2 ton 02 silverado to upgrade to a 2018 2500hd Silverado. Just would like some opinions on which Silverado to chose the 6.0 vorte...