We had a few people at the Edmonton sled show ask about a product like this. We did some searching and sourced these. We have them on our own trailer for a few months so far and they work great. If your interested drop us a pm.
Putting the ramp door up places the ramp in a vertical position and the hinged guides end up in horizontal position. The hinged guides shown are for enclosed trailers. There is another model available without hinges for open trailers