Slant 6 Turbo 68Dart Project
yea. run it right up next to your vent tube extension. it should run fine without it. may not even need to do it at all. my thought on it is that you would want the most pressure you can get in there to hold the power valve open against the pressure coming into the fuel bowl. did you block off the passage on the bottom of the carb that usually lets the vacuum into the power valve chamber? its going to act like a vacuum leak if not. might even make the power valve flutter from bleeding off the higher boost. or keep it from opening at all. what number power valve spring did you use? still running 10psi?
just keep an eye on the gauge when you get on it. it should start dropping normally into the richer afr's then all at once down to the target afr if the boost reference is working.