I just received a very old cel from the series 
Candy Candy.  The cel has the sketch stuck, and 
in some parts I can remove.  Im not sure if to 
continue removing the sketch or not, specially 
taking into consideration how old the cel is 
(it’s from the 70’s), and I don’t know if the 
painting can be damaged by doing so.

Can somebody with experience tell this new 
collector what to do?

Thanks!

Bulma Merquise