There's an unused altered Nomad Artillery model in the game that resembles the Original Marduk (yes it's almost identical to Ish'Tar but there's a slight difference), so I thought about giving it the Old Marduk turret placement (and a little bonus feature), plus some cosmetic changes. Reason is, I just think the OG Marduk is superior. The results are in this video.
All of the turret arcs are completely identical to the OG Marduk. Placement might be slightly different. Added in a heavy-hitting single FWG for extra flavor, used the Warwolf for demo purposes.
My suggestion is to either make it a separate entity (bonus headache for @Haste lol) or replace the Ish'Tar with this one. Me personally? I'd never miss the artillery ever. Not suggesting to update the OG Marduk itself because that would be sacrilegious.
Heavy Arcs + FWG
Primary Arcs
Secondary Arcs
The ship itself is entirely game-ready, with a corresponding .sur file already existing in the game files.