Not massively clued up on these hybrids but iv read a few things about them.
Ecu can be run piggy back if needed but a standalone would obviously be better. (What do local mappers prefer to use?)
Intakes. If you use a silvertop setup they run Afm so you would need the intake plenum and then a pipe to the afm and a filter on the front of it.
But with an ecu these could be setup to run a MAP sensor (blacktop) then the throttles can be run open if wanted (best results still seem to be with a plenum 50mm trumpets and CAI though)
Get a 5speed (c52 is 5speed i know lol) box they are generally stronger although 2nd n 3rd gear syncros do tend to be weak anyway but theres been plenty of boosted 4a's using them boxes so nothing to worry about. Just get an uprated clutch kit
Build wise, i can only say what iv read.
Should be built with a Porsche 944 cambelt iirc?
And to set the timing up spot on a set of vernier pulley's is needed.
Then the other thing is the way the crank is machined (oilways offset on journals) they aren't designed to take high rpms. This would be down to what you tell the tuner though.
Also im Not sure on torque settings or changes made to oil pumps etc