Here you have a problem.
I can check the numbers on the airflap and fuel distributer.
You can use a complete 928 injection.
When saab use the special plenum they used 911 turbo injectors.
But if you use orginal inlet manifold you can use orginal saab injectors whit (o-ring).
Injectors to k-jetronic don´t flow so much difference.
Check out the mercedes after market injector.