Al, As far as laying something down on the ramp, I think you should take a look at this post and its associated thread:
rollers and stuff

I am wondering if you can employ a long piece of rope to your tow vehicle. I am not sure of the distance you are talking about or if you can get the car in allignment. But if you can, I'd invite you to consider a concept I once came up with but never had a chance to try. Please take a look at the attached picture. Blow it up in your picture viewer for details. Let me know if you can make any sense of it.

This solo retrieval method might work with or without wheels under the boat.

GARY