Monitoring narrow-band AFR will tell you nothing. And it takes MAJOR mods to outflow your stock fueling and injectors.
SilverBullet and I both run asjustable FPR'*, but our 'applications' are a bit unique. We're flowing tons more through the engine.
Dude, looking at your mods, you can't possibly be outflowing your stock injectors, which would be the only logical reason you'd want to do this. Many L36'* have been modded further and still ran fine on stock injectors.
Mucking with fuel pressure is another variable your PCM and sensors have to overcome. I'd suggest staying away from an AFPR until you know for a fact that your injectors are going static before WOT.