I did this with my RL24 several years ago. It was surprisingly straight forward. Didn't need inflatable rollers - straight onto grass. Getting the boat back on the trailer was hard work on the winch - you leave the car in neutral, brake off and pull the trailer under the boat. Make sure everything is lined up straight before you get the boat on or off.
I removed the swing keel while it was off the trailer. Much harder than getting the boat on or off. You need a rope attached high on the mast to roll the boat sideways to remove the keel. The self righting capabilities of the RL24 make this much harder than you would think. The keel is VERY heavy and hard to move around.
Hope this helps,
I ended up disconnecting the trailer and attaching the rope to the towbar and using the car to roll it.....if you use mates, make sure you can tie the rope off against something when you are removing the keel - the boat will roll upright very quickly.