[travelin texans]

You'll need to ask here!
You will not receive/find any schematics for your RV or any other, Keystone considers that information proprietary. They don't have as builts & not entirely sure they have blue prints & if so the folks building them don't follow them. They seem to build them on the fly depending who's throwing them together on the line today, meaning there's typically not 2 built exactly the same.
Just FYI, the "polar" package you mentioned pretty much only consist of the corrugated plastic (coroplast) covering, so don't plan too heavily on using it in "polar" conditions.