Problem with anodes in the years 1800 Challenger ´1997

[Digitalia]

Good morning,

I have bought a 1800 Challenger in 1997.

I'm going to have the boat in salt water and I wanted to install sacrificial anodes.

The problem is that I do not know where the anodes are located on my boat.

Where do I install the anodes?.

I have the shop manual but the picture of the anode do not know where it is in my boat.

How much anodes must be installed?

Thank you very much