More loose binding

I have a 17 year old F5 mandolin with spirit varnish finish. The celluloid binding on the long curve on the bass side of the headstock is lifting in the middle. To complicate, the end of this section was previously re-attached with ACC, about an inch. The end under the small scroll is still attached. I'd prefer to reattach this with LMI binding cement which has worked great for me in past applications (including another spot on the same instrument) but I can't get a clean application of the adhesive with the end still attached. So the question is how to proceed. Should I carefully cut the ACC bond with a razor blade? I have a product called un-cure which does just that with ACC but I'm concerned that it will melt the celluloid or damage the varnish. I welcome any suggestions on how to proceed. Also, does acetone damage spirit varnish? Clean up of the binding cement is with acetone, although it works like a contact cement so there's no squeeze out if applied carefully so that's not a big problem.

Larry