Injector Selection Issue
What do you plan on using the engine for? Higher rpm? Racing? Street performance? Are you going to modify the engine at all? New cam? Better heads? E-85? All of those things require more fuel, and would require bigger injectors.
What ECU are you going to use? If you are going to use the stock ECU that came out of the Silverado, then new different injectors will require a new tune in the ECU, and a new mass flow meter (if you're using one).
If you are on stock cam, flow rate isn't going to be an issue with any of the stock injectors.

