I am about to install and edelbrock supercharger with the 3.5 pulley should be 7-8 lbs boost. Set up right now is a 2008 Silverado 4x4 on 35's with 4.56 gears, DoD delete, TSP 220r 114 lsa cam, gibson shorty headers, hollowed out cats, 2600 stall, knn intake right now. The edelbrock came with 36lb flex fuel injectors and I have a flex fuel pump to go in but from what I have read I don't think the 36's will be enough. Truck dynoed right at 300 whp with the above mods with 35's on, was thinking truck should be between 420-450 whp after supercharger. From what I have read on a 4x4 with 35's people are getting around 25% drive train loss. Also I have searched but yet to find a company that states that they include the injector data sheet with the injectors (maybe a Vendor?). I will be tuning this time around.

 

I would use FIC (fuel injector connection) they are great about the data and have great customer service with good prices.
A 42lbs injector would be boarder line. A 60lbs injector would be just about perfect with some room to grow. A 72 or 80lbs injector if you want a lot of room to grow.
Here is a link to the 60lbs I would buy in your situation.
Fuel Injector Connection Store