Sounds interesting.
I did this once before with my buddies Carver. It was on blocks in the back yard of the marina and we had to put a trailer under it. here is what we did, you just do it in reverse.
The transom had huge blocks under it so it was quite stable. We started by jacking up the hull with a floor jack and a big heavy flat piece of wood for cushioning. We backed the trailer up close to the floor jack and then lowered slowly. We re-set the jack a bit farther back and repeated the lift slightly, just enough to move the trailer a few more inches back. Repeated again until we were right up against the rear blocks. We then raised the boat at the rear, removed the blocks and gently loaded it on the trailer ready for splash.
If your going to take it off the trailer start with the rear blocking and raise the hull like I said with a floor jack and blocking wood and gradualy move trailer slowly in sections blocking as you go.
You should be able to do it in less then 10 minutes or so.
Don't know about your Marina but ours has a great big woodpile with huge blocks and lots of cut 2x6 and 2x10's so we hae a plethora of blocking material to choose from.
If you ever drive by a highway construction area and they are taking out the old wooden supports for the guardrail and replacing them with metal ones, ask the forman if you can grab the wood. They usually say yes as it saves them the hassle and you get all kinds of 8x8 free wood blocking material. I got a whole truckload of the stuff for nothing!!!
Have fun and play safe!