Quoted from ViperVS:You have to freeze the mylar and pull it off rapidly
I guess we all do things diffrently, but thats just crazy advice in my humble opinion.
If your going to remove mylar with the freeze method (which usually is the best method on games from this era) dont just rip it off, TAKE YOUR TIME.
Make sure the adhesive has frozen and pull slowly. Freeze, pull, repeat. Dont rush things like this.