It's kindof a crap shoot for this. You don't really know what's gonna ghost or not.
You can reglue inserts, but there is a risk of breaking them upon removal. Usually if it's stuck down, I leave it.

Some insert plastics react badly with clear. I believe HSA has something on their website about system 11 playfields being incompatible.

The fact is, we can strive for perfection, but all we can do is get close. No matter if you choose repro or restore, it will be better than what you had. If not, it wasn't bad enough to replace.