The last time I did my 23.5, I borrowed 4 stands from my local boatyard. I dropped the nose of the trailer down as far as it would go, Then put 2 stands under the stern. Cranked the nose of the trailer up which lifted the stern of the boat off the trailer. I put a jack under the bow and raised the bow some and dropped the nose of the trailer down until I could get a 6x6 across the frame of the trailer under the bow. I may have supported it on blocks on the ground instead of on the trailer frame. I think I ended up using just the pads from the other 2 jacks when I blocked up a couple of supports from the 6x6 to each side of the bow...nothing elaborate. I don't remember just what I came up with, but the boat rested fine on just the 2 at the stern and support at the bow. there was no way to put more stands in place with the trailer in the way. I removed the bunks from the trailer for access and left the trailer in place. I also seem to remember letting the air out of the trailer tires for some reason...I wish I could remember why...I'm thinking that tolerances were tight enough that it made it easier to remove and replace the bunks.