US278 MS6 will change to two lane at Batesville, Ms not a bad road just have to watch out for the farmers and farm equip. US49/61 north at Clarkdale is 4 lane until you turn left on US49 then back to two lane to go over river bridge at Helena/W. Helena Ar. from there Us 49 is a 4 lanes for about 10 miles then turns to a combination 2/3 lane to Brinkley Ar. US70/I40.
You have two places to stay on that route one would be at John Kyle SP at Sardis Lake between Oxford and Batesville, Ms and the other is in a RV park in W. Helena Ar. south side of hwy headed out of W. Helena.
Hope this helps you.
John
P.S. could dry camp at the casino(s) at the river bridge.