Many DPs with a front door put the hinge on the front side and flip forward out of the way. I think rather than using angle iron and trying to paint it to look good, I would just screw a flat board to the inside of the step well and then finish it with stain to match the rest of the wood inside the coach. Then it will look like a piece of normal wood trim, rather than a piece of welded angle iron with paint on it. I would probably also just use a wood board for the floor, rather covering it with vinyl. Time you start putting covering over it may make it more bulky and heavy. Also that mean edging that will get banged up when dropping into place, or stashing out of the way. Just a nicely finished 3/4 inch thick piece of oak would do. Maybe even cut a slot in the middle of it for your hand, so it is easy to pick up and stash out of the way when not in use. My opinion is that as soon as you try to put a hinge on it, that just gives something that will wear out - not that the hinge its self will wear, but that over time the attachment screws will work loose and it will lose its fit and finish. Keep it simple to reduce wear and make it easy to use.