Hi Jake
I am probably not the best person to fully advise .... I come from an age when engines were clockwork, well nearly, my first car had a starting handle
Guess it is all going to be down to the amount of money you want to spend to achieve the performance you desire !!??
Cheapest
Stock ECU & original OEM set up ( If you can get it all to run ) .... Blacktop fuel injectors shoud be reasonably cheap if got at the breakers.
Mid price
Ditch the injection & go with bike carbs n Megajolt.
Suzuki GSXR carbs are quite popular as they are relatively easy to respace to fit a bespoke inlet manifold.
You'll have to resolve any carb jetting issues & emissions can be a problem to get, spot on for a road car ( Probably wont be an issue for you if your car is going to be for track use )
Most costly
Jenvy or bike throttle bodies with aftermarket ECU.
More or less a case of, how deep is your pocket ?? or how competitive do you want to be ??