@waternut, I have a cantilever (Hewitt) as well. I made up a temporary reverse winch system that winches the cantilever down. Made a bracket to mount a regular trailer winch that bolts to the same post as the wheel operated up winch is, couple screw eyes in the frame at the bottom, 2 holes in the cantilever arms, 3 sailing pulleys with snap links and some good rope. We crank it up all the way, slide some dock floats under the bunks, Tubes like @OB uses will work too, slack off the up cable and crank it down. Rises the lift right out of the muck, float it to shore and haul it out. Has worked great for 5 seasons. It is a little heavier on the winch corner so we offset the dock floats to that side.
That said, just 5 minutes ago I ordered the lift helper from Tim as I have moved my lift to an area that is much shallower and I want the lift frame to be up higher to make it easier to get close to shore. With the lifthelper it should basically be floating on the surface as opposed to below the water line. If I didn't move I would have kept using my old system.