We took down a few of the sections of ceiling from the back of the bus and removed all of the insulation that was there.  It was in pretty good shape, so I'm still not sure how much benefit we will get from the switch from fiberglass to foam insulation, but for some reason, I was convinced by all of the on-line "must insulate to the Nth degree" crud...  To me I don't see how it could make THAT much of a difference, but it appears to be popular consensus and I don't claim to be any kind of expert on insulating materials...

After trying to get the plastic strip to hold the roof for over 2 hours, we finally gave up on it.  The ceiling sections were so far apart that we couldn't get the plastic strips to stay on both sections long enough to screw them in place.  The ceiling panels are just too sloppy to fit right with the panel strips.

We ended up starting over and put back all of the old metal strips that originally held the ceiling in place.  It was quite a let down, but we'll work around the existing strips until we come up with a better solution.  In the mean time, we'll return the plastic stripping that we didn't use and move ahead with insulating the rest of the roof.  We don't have time to goof around all day trying out all sorts of possible solutions, so we'll come back to it later on.