I've only manned the guns (CA and CV) in ship to ship battles twice, but what I found worked for me is this;
1 - Take broad range changes at first to bracket the tgt, ie, fire at 4k, if short fire at 5k, etc, until you have the last 2 salvos on both sides of the tgt.
2 - Range in with smaller increments, about 1/2 of the initial changes. Keep splitting the difference by 1/2 of the previous until you're hitting, or see that the last 2 salvos landed on the same side of the tgt - if this happens, repeat step 1.
3 - For ships, be very aware of your direction and the tgt direction. I think fleets are moving at 40 kts/mph/whatever, so it's a darn fast change if both fleets are closing.
4 - Practice any chance you find - maybe offline if you can set the cv's close to each other?
In both fleet engagements, by the time I was able to man the guns the ships were rather close, and I was able to get hits. You might want to try using the AA guns, set to HE, since they fire a lot faster than the 8" guns on the CA.
Cheers