Once upon a time...........
I had bought a fishing boat and trailer package.
I wanted to paint the hull and while I was slithering @ under the boat/trailer, I noticed my bunks were SHOT!
I was jacking up the boat with blocks and 4X4's, 2X4 and a pile of bracing.
A old guy who walks his dawg by my place EVERY day stopped to watch the show.
After a few minutes of jacking the fore, blocking, jacking aft, he asked me, "why don't you just up the TRAILER, block the boat and lower the trailer"?
I finished my lifting and did the work.
Later that summer I bought a sailboat and wanted to refurbish the trailer.
I did his method, I gotta tell you it worked a whole lot better, safer!
I lowered the crank to raise aft, jacked it up a bit more with a floor jack, blocked the trailer up, cranked the front of the trailer and a used a jack to get it wheel off the ground, braced the boat with some 4X4 X8' on sturdy cinder blocks, lowered the crank and pulled the trailer from under the boat!
Was easy, and SAFE.
I found it much easier to replace the bunks and carpet as a pair, as the old carpet is pretty beat by the time you get to it.
I paint my pressure treated wood with oil based paint, cuz the modern pressure treated "stuff" isn't much good! (I did use 2 layers of plastic decking planks on a boat trailer and they worked well, slick side up)!!
I also spray silcone on my bunk carpets to make it easier to slide on, "wet the bunks before pulling the boat onto the trailer too!
Joe
Just my 2 cents!
As always take any advice I give with a can of beer er 2!