These 3M discs removes gaskets and old silicone without damaging mating surfaces.
They are especially good and easy on aluminum surfaces where you don't want to chance scaring the sealing surfaces.
You will need to have a standard high speed 1/4" air grinder to use them as they don't function at lower speeds.
https://www.3m.com/3M/en_US/p/d/b40064937/Google 3MRoloc Bristle Discs
Plenty of them and holder available online.
3M 048011-18730 3M-18730 Roloc Bristle Disc Grade-50, Size-2, Green (50 grit)
Used on automotive aluminum and metal
Diameter: 2 Inches
Rotates and spins at maximum speed of 25000 RPM
3M 048011-18733 3M-18733 Roloc Bristle Disc Grade-120, Size-2, White (120 grit)
2 Inch Disc Pad Holder with ¼” Shank, Die Grinder Sanding Suitable for Roloc, Quick Change Medium Disc Attachments for Polishing, Sanding and Surface Preparation, – by Ram Pro


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