Can the 4.3 TBI units work in a blow through turbo design? What kind of engine management system?
Yes for low boost app's, the only kink is the stock fuel pressure reg (FPR)will have to be removed/defeated and an external boost referenced fuel pressure reg. installed. I would tend to use a TBI off of a 350 cop car (bigger injectors) for a boost app. This ensure you have enough fuel capacity. Note that unlike a blow through carb set up where the the pressure drop across the venturi compensate with more fuel flow, an injection system is insensitive to flow and the injector have to be sized correctly to avoid going lean.
use this
(HP * 0.55)/number of injectors == lbs/hour injector size
e.g. 300 HP *.55 /2 == 82.5 lbs/hr << use a 454 TBI injectors in this case. They are about 85 lbs/hr.
As for EFI control lowest cost is megasquirt (MS2. There is an adapter that allow the MS2 board to plug directly into the GM harness for a TBI system with no wire mod's. These days you can buy a ready built MS system. A $100 laptop running windows XP is perfect for use to tune the unit up.
There are other EFI systems such as holley out there but cost more $$$.
Other than fixing the FPR the hardest part is running the fuel line/pump install especially if you choose to run hard line.
Hope this helps.
