Help with roof and trim please!

Hey!
So we were plugging along on our TD but have come to a stall. Nowhere in Fort Worth seems to have aluminium sheeting and I found a place where I could get a 4x10 for $62 for .032 only for them to tell me it's not going to work for my project. Plus there's nothing they have I can use for trim to cover the extra 1/4" (roof is 48 1/2" wide since I have a sandwich wall with 1/4" outside the trailer frame.
On the blogs and build journals I haven't been able to find how to do just the roof in aluminium. I'm thinking maybe forgoing the whole aluminum roof but I still need a type of trim. With my mural design I'm painting I think the aluminum roof will look better plus be more durable. Open to other options though!!
I'll try to get a picture of my design up.
So we were plugging along on our TD but have come to a stall. Nowhere in Fort Worth seems to have aluminium sheeting and I found a place where I could get a 4x10 for $62 for .032 only for them to tell me it's not going to work for my project. Plus there's nothing they have I can use for trim to cover the extra 1/4" (roof is 48 1/2" wide since I have a sandwich wall with 1/4" outside the trailer frame.
On the blogs and build journals I haven't been able to find how to do just the roof in aluminium. I'm thinking maybe forgoing the whole aluminum roof but I still need a type of trim. With my mural design I'm painting I think the aluminum roof will look better plus be more durable. Open to other options though!!
I'll try to get a picture of my design up.