I've been doing 'other things' so this went on a backburner but this is essentially what I'll try. There will be a TWO inch spacer above this and then one additional change was Scott buying the INDY "EFI" 2 AFB top which spreads the carbs apart a touch more so they are better over each runner. Talked with a few that run the modman and run well and there some basically unmodified in the plenum. That said, we could baseline it without the plenum mods..AH, NO!