The cardboard idea got a lot of flack when I did this last year, but it's still holding up just as good as ever.
As for getting into the window, all I have to do in my case is peel back the deadener and pull off the cardboard pieces. Done.
Yes, separating front waves from rear waves is what I've been preaching for a year now; glad someone finally listened.
The weather stripping stuff works like a charm.
Mike, it seems you did everything I've suggested in other threads.