Bob,
The only thing I bought from USP are the car sides. The rounded roof end is just thick pieces of Evergreen styrene glued to the roof end, sawed and sanded to shape.
I wouldn't be sure what kind of glue to use to attach long pieces of styrene to aluminum. On the first ALW kits I built, I just used regular old Testors liquid cement. Unfortunately after a few years the sides start to bow inward. No doubt a long term affect of the glue. That's what happened to my first attempt at the blunt end observation. I put it together and then put it aside for several years and the sides bowed inward so bad that the roof wouldn't fit. However, other cars have worked out pretty good. Once fully assembled some bowing appears but its really not visible unless you take the roof off.
These latest cars have the the inside car side reinforcement styrene glued on with CA. Everything else including the fluting is glued with Testors styrene cement.
Ken
