Im not sure here but... if they are low impedance ~2ohms then its just a matter of tuning them up with the safc?
Does the safc allow you to select injectors from a menu??
If it does that might be a problem. 50lb is like around 500cc? so im not sure??
I think the main thing is that they are low impedance to match up with the stock setup then its just a matter of tuning them.
Msd's are different to the denso style injector commonly used on our cars it uses a ball to atomise the fuel instead of a needle. The msd's atomise the fuel better. But are less reliable. So i doubt you could just select 500cc injectors from the menu and it will work perfectly.