AC compressor rattling

  1. My model of MX-5 is: eunos na 1.6
  2. I’m based near: Inverness
  3. I’m looking for technical help or recommendations on:

The front of the AC compressor is loose and rattling when the engine is on. I have tried tightening the bolt in the centre but it doesn’t seem to help.
Any suggestions on how to tighten it?

Looking around a few sources reference compressor rattle as failing internals and an inevitable product of wear and age.