AAT code Audi A6 2.5 TDi motor upgrades

I have recently bought an Audi A6 2.5 TDI AAT code engine.
I'd like to up the power and the only differences I can find on Etka between the AAT and AEL are the injectors and the ECU.
Can anyone tell me if there are any other differences?
What kind of hp will the KKK K16 be up to and should I look to replace it?
Also what other injectors can I use in this engine which have a higher flow rate?
Has someone put together an Injector Flow rate page?
Thanks
Mike

Hi, i have a 1996 A6 tdi 2.5 , its a red I and it flys, its 140bhp so it might be worth ya getting ecu and injectors for one of these maybe.