I'm working on my S5 NA swap in my GSL-SE and need to do something about injectors.

For now, I plan on blocking off the secondary injector ports in the S5 intake and running the GSL-SE primaries only, with the GSL-SE ECM and all. Since the injectors are S3 and the engine is S5, what diffusers should I buy? What other parts should I be replacing just so I cover all the bases, like the upper grommet, lower grommet, etc?

 

i think i'd run the S5 diffusers, or in reality i'd run the ones i had. i would replace all the o rings and stuff, just run the GSL-SE fuel rail (if it clears)