Sometimes its not the individual site length but narrow interior roads, sharp turns and limited room to either back into a site or pull out of.
I you want to give it a shot do you home work beyond picking a park and camp site. Use the available satellite or birds eye aerial view of the camp ground. Check the interior roads, turns and such. Give the prospective camp ground a call. Many times the contact station and phones are manned by work-campers who will understand what you are asking.
90% of my outings are government facilities and even with my 30' home on wheels I check new park out as much as possible. A pull thru site is no guarantee either if your rig can't make the turn to avoid the drainage ditches, trees, site markers, boulders and such on both sides of the road.