I know it's an old thread but Thanks to both of you for your designs.
I just picked up my TM a few weeks ago & I also have 2 dogs that are used to the bed at night, at home and in the old trailer. Both are old and short! They are also used to using an old ottoman to get into the bed at home. But that's not quite high enough for them to get into this one!
I have picked up a used telescoping ramp (didn't cost much and could be helpful in the truck) that might be workable for them (though the old black dog is VERY resistant to change - novelty is not high on her list!) and the narrower width might put them both off. I can always re-sell it if it doesn't work in the truck.
I think they would be more comfortable with the step-up type of arrangement they are accustomed to, and your designs are exactly the kind of thing I was looking for, and chewing around in my mind. They go the full width of the "hallway" space, so it's safe and doesn't give them a "go around it" option (or over it, which is my biggest concern when they disembark), and the depth of the treads are nice and deep - really important for dogs, especially when they are going back down.
Workable for both the pups and my short a** to get into a bed that was MUCH taller than I expected it to be.