The horn in my daughter's '96 C280 sounds sometimes
when turning the steering wheel and you can hear
something rattling around inside.

Getting at the source of the rattle seems to a bit tricky.
It looks like the 'housing' on the steering column is
attached with two torx fasteners.

Is this the piece that needs to be removed? If yes, does
anybody know the size/type of the fasteners?

If no, how do I go about removing the housing and/or
getting at the horn mechanism?

Thanks,
Forrest