All-Balsa Super Chipmunk 40 - 64"

I recently picked up a great condition chipmunk airframe. I don't believe it has ever flown. I am in need of the manual or at least the CG on this model.
Can anyone lend a hand? It would be awesome to get it flying! I am considering converting it to electric for simplicity. However, I would need to cut an access panel for the battery compartment [not a huge deal].

Thanks and I look forward to hearing more from this great community.

https://cimg9.ibsrv.net/gimg/www.rcu...f13d35fc9.jpeg