Rick,
You could go to Home depot and buy a small 30 amp breaker box without the outlet on the back. But you could hard wire the converter right into the box. It's very easy to wire these boxes as long as you follow that diagram I posted. All you really need is a box that will hold 3 or 4 breakers. You will need to change to a 30 amp power cord to plug in to the campground power pole. My cord plugs into a outlet on the outside of my trailer, then i can just roll it up when i'm ready to leave and store it under the bench seat. I posted a picture of that outlet.