Ah!
Jeremy,
in my excitment to post I forgot to answer your question!
As you may know I have reviewed your kit right here on MSW.
Bronco Akula is unfortunately a mixed-result effort to represent the Gepard.
If you want to turn it into a "generic" Akula, as you say, your best bet would be to turn it into the Vepr (K-157) which is, to my knowledge, the only Akula II boat. This is due to the fact that only these two boats have a longer hull, also most of the fittings of the Bronco kit - not to mention the shape of the sail - would look more correct for Vepr than for Gepard anyhow!
In order to do this, only a very minor change would be required: you would need to source or scratch a towed array pod to fit on top of the stern upper rudder. This would have been a very minor and easy thing to do for Bronco but somehow they stubbornly concentrated on the "Gepard"
Your best chance would be to try and see if you can find the old and now OOP Akula kit by Alanger (there is one up on e-bay now) and use the rudder+pod from that kit: be warned that this may take some effort.
Then, if you are really into rivet counting, you would also have to add a raised lip where the doors of the communication buoy housing meet (this is a hatch in the centerline, just aft of the sail).
I hope this helps.