barrels
When I did mine I used two 55 gal drums at the transom, I put a 2 X 8 with a boogie board on it and let the transom set at the middle of the barrels. I used a 4 X 6 X 14' for the front. I let the trailer jack all the way down then placed the barrels under the transom raised the jack as high as it would go then blocked the tongue and raised it the final amount placed the 4 x 6 under I used concrete blocks to hold the 4x6, let the trailer down then pull it out. Let the keel down on the ground afterward. If you were close you could use my stuff I still have it.

Since I had to keep my boat off the trailer all summer I made pads for the front. To put it back on the trailer reverse the process.