Personally, I wouldn't bother putting any shield mods on Retribution and use the shield fairly sparingly.
Kinetics being in the smalls is fine imo, because shields don't care about hit strength like armour does.
I'd prefer railguns rather than autocannons though, which would also work better with the PDAI.
Rangefinder doesn't boost PD weapons, so it's not actually doing anything on that build, because the PDAI has flagged all those small guns as PD.
Pull it off and replace the front vulcans with 2 dual flaks, and 2 kinetic medium guns. Hv. autocannons might be nice for the dps.
With the remaining OP you can max out vents, and add armoured weapons, auto repair unit and flux distributor.
1350 dissipation with your weapons generating 2225, which is managable.
Especially if your primary control group is the hellbores as that's 750 flux/s you can manage directly, leaving 1475 flux/s.
It is also worth considering using the large mounts for storm needlers and/or devastators, and then building around those.