removing inside pry marks

[stinger haut]

I tumbled a Buffum's soda with the inverted lip. It turned out near mint to my surprise. However, there are deep pry marks that were dicovered when the bottle was finished tumbling. They are all on the inside of the neck area. I can't reach them by hand because the neck is smaller at the top then flares outward. I could cut with 600 grit but I have a nice unpopped big bubble below the pry marks that would definitely burst with any cutting oxide.
Any ideas on how to shield below the bubble and cut with the cutting oxide?

 

[Bottle tumbler]

i would use an open tumble on this one. wayne has a stopple for this. then the copper can go right through the mouth instead of being stopped by the cone stopple, i would use 1200 and then poilsh.

rick