5.3l SD Start up tune?

Hey everyone, new to the forum and HPTuners. Early this summer I will be completing a 5.3L turbo ls swap in my 2016 Subaru BRZ. I have an E38 ECU. As of right now I don?t have the tune file that?s on it nor do I know what vehicle it came out of. I believe it was a truck though.
I?m looking to run flex fuel with an ethanol content sensor, speed density, with an OEM LSA MAP sensor, ID1000 injectors, pretty aggressive cam (54-477-11) and a Dorman intake manifold.

I?m a novice to tuning but not a beginner. I used to tune my Subaru STi a few years back making around 500AWHP. But this is completely different software.

I?m looking for any advice or possible a start up tune.

Thanks everyone.

This is a gen4 engine by the way.

Not knowing what E38 you have makes it tough to give suggestions.

There is a big difference in the early computers and the later computers as far as what you have to do with them to make them run in speed density and with larger injectors.

Ideally it would be a late model ecu because it has the higher hard coded injector limit than the earlier ones correct?

Right, I know for sure that 2010+ will have a 127lb/hr injector limit before you need to scale it.

Turns out I have the later year E38 with the higher injector limit. I noticed I don?t have the option for the 2BAR OS. It?s sourced from a 2010 Silverado 4.8l fleet vehicle apparently. Do I need to flash a similar year OS that has the SD OS option?
Thanks