I`ve used these , made by Happi jack on several trucks and campers
https://store.lci1.com/fm-fgl9-centering-guide-locks-front-only
For the front ,there supposed to go on their braces , but I`ve screwed them on a 2x6 fit between front hooks on a Dodge .
I don't remember them costing that much , last time I bought a pair
I have a pair mounted to short pieces of 4" steel angle on my flatbed now , with short lengths of same angle perpendicular to the camper at the back ,cut at 45 degree at the top to fish the camper into as it drops
If you have round rubber bumpers on the front of the camper , you can remove them and mount them to a board or steel / alum the width of the camper and put a piece of abs on the camper to cover the hole and as a slide
Its nice to drop the camper on the truck and not have to adjust the fast guns or turnbuckles when its in the same place every time