The rules reference says that attacker's hull zone does not block line of sight. Does this mean that if I have a target on the physical right side of my attacking ship, I can use the left side guns to fire at it? Or can can I use my right side guns to fire at a target directly behind my attacking ship? Even if, in both of those cases, I would be firing through hull zones?

In short, No, you have to still be in arc.

longer answer, remember there are multiple tests you need to complete to shoot.

am I in arc?

do I have LOS?

am I in range (in arc)?

The ruling there is telling you about the second point, where you are tracing Los dot to Los dot. That line can cross over your own different arc.

tbis can happen when, day, you are using a side arc to shoot st someone who is mostly in your front... you can draw arc to the very back portion of their arc - even just a sliver is enough... but since their LOS dot is further forward, it might be well into your front arc. The shot is still allowed as long as you comply with all the points

31 minutes ago, RG1701 said:

The rules reference says that attacker's hull zone does not block line of sight. Does this mean that if I have a target on the physical right side of my attacking ship, I can use the left side guns to fire at it?

Definitely no. Your target has to be in your attacking ship's firing arc.

https://starwars-armada.fandom.com/wiki/Targeting

You can fire "through your own hull zone," but it doesn't happen that often. See this thread for an example. See how the MC30's right and left hull zones have a shot on the ISD's front hull zone. But it wouldn't work if the ISD's hull zone was not in the firing arc.

BTW you can ask rules questions here. https://community.fantasyflightgames.com/forum/440-star-wars-armada-rules-questions/