They call it "bilge loading" where I work. The first roll goes in and they put 2 wedge shaped blocks under it, all the lower rolls get the blocks. The last roll on the truck gets those blocks nailed down to the trailer floor. Once the first roll has it's blocks removed we use a 4' long wooden "bar" to work that roll out till the one on top drops down. Very much like this video I found:
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Where I work the rolls roll off the truck onto the dock and about 4' later they drop into a special roll elevator that takes them to the basement where they automatically roll off and the guy grabs it with a clamp truck. Then we rotate and stack them normally. Every once in a while the roll show up stacked flat. We have the driver go around the building to another dock and we use a tow motor and a freight elevator to unload them one at a time. It is a pain in the a$$hat.
Our press is now 44" wide so a 44" roll is a "full roll", 33" is a 3/4 roll, and 22" is a half roll. Half rolls come with two packages together so they are the same size as a full roll. We also have "dink" rolls that are 11" wide they are packaged with 2 or 4 roll together.