I use straight boat trailer rollers! You can usually find a 12" piece for about $10. I cut them in 1" & 1/2" sections with my miter saw. I also use the same for motor mounts!
Boat trailer rollers are a good idea. I have some old conveyor belt I used in my 31 for body and motor mounts...6 years and 50,000+ miles and still in good shape.