Sounds crude but also have used plywood with eyebolts in the appropriate spots (depending on the size of the plane). Then use bungy cords wrapped around the landing gear on the front and over the rear of the fuse, hooking them into the eye bolts. On some, also around prop area. Have transported .40's, .60's, 1.20's and even 1/3rd this way in open pick-up and could go 70+. Get tougher with multiple planes if larger as you run out of bed space, so the rack idea is great here.