1969 Dart Street/Strip (Re)Build

I've asked a lot of people about runout and very very few know anything about it or have ever measured it. But the ones that did know said I'm definitely going to feel the pedal on that, contrary to what only one person at Wilwood told me. I hope we're all wrong but I won't know till I drive it. So I've been busting tail the last several days to get it together. Almost there now. Carb linkage, starter, headers, steering joints, and brake bleed are all I lack at this point. I'm only 2 bolts from dropping the exhaust so I may lose that and drive it, loud as hell. Through the cutouts is noisy, but the open headers are a whole new level. I need it out of the way anyhow to drop the driveshaft so there's my reason lol.