If you can't use T2 gun, then use 250mm Prototype Gauss Gun ; remove T2 ammo and keep the navy ones.
Last high slot is for t1 Link module. If you have skills you pick the one you have skill for with the 3 boost charges.
If you have the 3 links skills ; Shield & Infos are the most important (Shield all boost & Info sensor)
OSPREY
KERES
HYENA
EFT
there should be text here some of the time but i'm working on it
Spectre Fleet