I took the plywood off this morning. It came out real nice and I am quite happy with the result. It is quite flat and very stuck. I highly recommend the G/flex as it dries rock hard. Yet the manufacturer says it will remain flexible enough to not loosen up with movement going down the road.
The packing tape is a bit of a chore to remove as most of the tape adhesive remains but it did the job. I will clean it up with some solvent.
This was the worst area on the rv and in the remaining areas I will replace very little of the luan. Maybe just some around the edges.
I will eventually remove and reseal all trim and storage doors. I think I will do the windows a few at a time too. I really like the layout of this rv and it would take a lot of money to improve upon it. I will post some more pictures when there is more results to show.