I am curious what compression joint you are going to be using? You are making good progress here and very helpful for a new guy like me so thank you in advance.

Also, interesting you brought up that MAF boss. I have an entire drawer of essentially throw away metric and SAE screws that have come with bits and pieces over the years. I tried several of them and couldn't get anything to thread into mine, so go figure. It's almost like the threads are galled or something. Maybe someone else will ring in with a definitive?