That's the problem and where 40 years of hands on hard learned experience come in JSNE.......

I face this problem every week and sometimes you end up spoiling something. If I was you I would VERY CAREFULLY play heat around the rim of the ocular lens counter cell. Too much will destroy the lens joining the lens parts together. When it is hot to the touch, press the serrated edge hard down into a leather pad to grip and then try rotating. Same as the OG end but you can wrap a leather band around the shade and grip it with suitable grips to unscrew.

But what do you want to strip it for?