Looks like on top they're guns and then below the tail guns is the missle compartment, both seen in AOTC during the dogfight with Obi-Wan and should've been on Jango's ship too.
I'll be buying this ship because I passed on the POTF2 version.
Talk Show Host Interviewing Joker: “Your said to have only killed about 600 people Joker. Now don’t take this the wrong way but I think you’ve been holding out on us.”
Joker: “I don’t keep count. I’m going to kill everyone in this room.”
It looks like those are little snap-on pieces as well...