I would stick with the ball and disk.
As for the injector choice.
There are many variables to make that choice.
If you are going to use dsmlink or aem then go as big as you want.
I use fic 850`s. They worked well on the 16g and are working fine on the gt35 w/ alcahol injection. On just pump gas with the gt35 you would want a much bigger injector.
If I was to buy them again I would just get 1600`s.