Cry for help - scope cleaning

I hope someone can give me some advise here.....

Anyway, today I went to clean my very grimy LX200 corrector plate and
after an initial wash with isopropyl alcohol & distilled water, I
painted it with collodion to get the remaining bits off.....

Now, I've succesfully used collodion on several occasions with smaller
optics, but this time it didn't come off cleanly (maybe 2-3% has stayed
behind and now doesn't want to come off), and where it has come off,
the surface is pretty mucky and smeary.

Any ideas what to do next? Should I paint another thicker coat over it
and try again, or can i dissolve it off with more alcohol and go about
it that way.

I think I will take the corrector plate off tomorrow to make life
easier, but wuld appreciate any tips on how to clean ff the remaining
collodion.

Thanks!