I'll have to look back in my thread to see if I recall. But I drilled and tapped all the ports on mine, but did break one tap because I got greedy.
Use lube, go slow. And periodically clean and test fit.
I used 1/8 and 1/4 npt for the various barb fittings I installed. The vac tree MIGHT be 3/8 npt. Same as intake sensor but need to confirm
curious why you tapped and put a barb fitting in that front one next to the pvc valve connection, since that would be the same one as the one that sticks out further on the Exploiter intake that was said could be capped. But looking at my photo of my stock intake there is not a cap on mine and appears it had a hose on it, so now I'm confused on what went there...