Need a check on my Nitrous Barracuda setup

I'd use some MS109 for certain. No octane boosters for this guy. Those plugs do look like non-projected tip.

As far as RPM range....how far do you expect it to fall back between gears shifting at 6k? I'd hope it stays above 4000? Forgive me, I am a 4-speed guy so there might be some ignorance to what happens when a gear is missing.