scott i think if you post pics it will be easier to visualize.
If you have access to a pontoon you can probably rig something up. I've also heard of running 2x4 across a jon boat. not sure how big they would have to be but you could also use mooring buoys or inflated fat sacs if you can tie them to the lift to support the weight so its not so heavy and to mitigate the risk of it falling and sinking if you lose control of it.
here is how the pros do it: note this is a floating lift, but the key it proping up or supporting the weight for you situation, right?