I'm going to start my CFII add on. Are there any good books that go into good details about flight instruments?

pilots handbook of aeronauctical knowledge..what i like to call the one stop shop. published by the FAA. Hmmm i wonder what material the FAA wants you to know?

ASA instrument oral exam guide is a great book for the CFII

Instrument Flying Handbook is a good one too

Thanks for all these great posts. Its about time for me to add the CFII to my active CFI ticket . Any more advice and personal experiences be appreciated.