When loading containers we have been having to use a roller pipe I made a couple years back
this served the purpose much like the Egyptians moving blocks of stone. The problem with them was you could not haul with the rollers under the container so it had to be raised on one end and dunnage put under it Like I said it worked BUT!
so today before Bob left we made 4 slide blocks to pin in the 4 corner pockets all he will have to do now is winch a container a little ways onto the trailer use the hydraulics to raise the tail of the trailer off the ground allowing enough room to insert the slide blocs in the front of it then they will slide on the steel rails of the trailer. for a 40 foot container he will only need to use 2 of them as the rear of the container will not be sliding on the deck of the trailer but for the shorter 20 footers that usually have Large generators mounted in them once he winches them so far on to the trailer he will pin in the other 2 pads and winch it further up on the bed