The vacuum port that you are using now will cause cylinder #1 to run lean
all the time. That port is only meant to run the vacuum pods on your factory air cleaner base.
Get the correct PCV fitting that fits in that vacuum port that is plugged with the pipe plug just in front of and under your carbs fuel inlet.
https://www.inlinetube.com/products/inl11220
That fitting is designed to meter the fumes from the PCV to both planes of the intake so neither side runs too lean.
It
will make a difference.