Well it turns out it was a very simple job after all. I noticed it had raised slightly at one side so I dribbled a little lighter fluid in there and waited a few minutes. Then I prised it off with a small screwdriver. A tiny bit of enamel came off but I’m not worried about that.
It was a very weird white, sticky residue. Maybe something like crafts glue. I’m not sure really.
Perhaps a little acetone to see if it'll soften the glue's molecular bonds?
It's always a bit of a gamble if you don't know what kind of glue it is, but I don't see how acetone will damage the platter. I've used it to clean bearings and bushings
Other LH users can jump in if they know of a better one to suggest
