I have a chance to buy a grandby and I looked at your build but have a question hopefully I can explain . The rear of the camper where it goes from 48 to 60 it hits where tailgate shuts. If I can cut the plywood making another step in like 2 on each side , is it only plywood thT I have to deal with? I don't need to make the entire piece that small or is there metal wall tied to it? I have a truck camper so I know the outer wall is on the outside. And on this model I think that's the same and there is just plywood to deal with. I'm a carpenter so no biggie for me it's just hard to pass on this in north east . Thanks for info