Replacing damper felts and hammer tips - how clean is clean enough?

[kevinplaystheblues]

Started cleaning my dampers and hammers tonight ahead of replacing. Pictured are my 'first slice' clean cut removals. Neither are super clean.

The felts seem to have been attached with a somewhat messy glue, but they might be candidates for acetone or thinner if required (have to check aluminium reactions) but I wouldn't think this residue should effect the new felts much?

As for the hammers, chemicals are obviously out. The hammers themselves sit kinda unevenly anyway, so I would think a little bit of residue would be lost in the noise, but happy to be corrected.

Advice appreciated!