Keith, if you do a lot off camber campering, I’d recommend getting four camper guides to keep the box centered. This takes a lot of pressure off the tie downs. I have used Lance’s version for 19 years and two campers to good avail, but there are newer better ones. With a Ford F series truck, the cab is too tall for most campers to clear. But you already know this. My bro has an F-250 and used a 3 or 4 inch by 4×8 foot closed cell foam pad for under cement sidewalks as a riser. It works fine, adds insulation to the floor and doesn’t weigh much.
For folks without a Ford i recommend a spray on bed liner and a thin (like 3/8 inch) sticky rubber bed mat. Thick bed mats tend to make the camper box sway, pitch, and yaw.
2020 Ford F-350 XLT FX4 4WD SRW SB SC 7.3L Godzilla Gas TorqShift 10R140 397 amps dual Alt dual batts Frnt Dana 60; Rr Dana M275 E-locker 4.30's 4580/4320/4066# payload 7243# curb wt. 11,300# GVWR 5-er prepped. 2020 Northstar Laredo SC, 12v compressor fridge, cassette, 320w Solar sub zero insulation.