I was reading a post on rcscale builder on a bates P40 They were installing the windows behind the cockpit. It was a fiberglass body. They said they glued styrene strips to the inside to form a lip to attach the windows to. They did not go into further detail. I am wondering what they did a bout the strips showing . why not just glue the window in from the inside I would appreciate any help-I am building that plane

Sounds like someone went to some extra work adding strips. Perhaps he had a good reason, but gluing directly to the inside is fine. Make sure you use a glue that will adhere properly.

Perhaps they had window material the same thickness as the frame, and wanted the windows to be flush. In that event, a 1/16" wide ledge of transparent styrene wouldn't show, very much.

I did something like that, putting flush windows in a BUSA 25% Cub. Turned out nice, you can see the backup pieces if you look closely. The glazing is nice and flush.

I would think the shape of the rear side windows on the P40 would make the flush window approach pretty labor intense.

Best wishes,
Dave Olson