Hi Cars, I just thought of something that might work good for you once you get the rest of the covering off sand it light then run a tack cloth on it. Then get you some Coverite Balsa Right and coat the airframe with it. BTW do this in a well vented area as it gets pretty strong in the a close space. Then let it dry and cover it to your liking. There are sever tutorials online on covering an airframe.
Good luck
Michael Johnston