In any written brochures look for the term, Big Rig Sites.
If you don't see that in the write up call the park and ask if they have Big Rig Sites.
A pull thru will sometimes work, but I've seen some short pull thru sites also.
Something else I've run across is you tell them your trailer length and they think that's you total length, find your total length, truck and trailer, and convey that length to them, saves you much confusion later.
I dealt with some really out to lunch people taking reservations in some parks.
Good Luck & welcome to Heartland.
Hockster