That's funny, I live in Chelmsford....not even ten minutes from you.
Flagged as in the OBD2 machine marks you down in the State registry as being illegal and you need to go to a state run center called a MAC center.
There , your car is put through a full visual inspection on a lift where someone will point out every single thing on the car thats not up to state code. Trust me, you do NOT want this. I had a friend with long tubes that the MAC center made him put his stock stuff back on in order to pass inspection, again not good.
The good news is we have a friend ( on this site ) that runs a local shop in Pepprell, he has a twin turbo 2v GT. Many of us ( including me) have gone to him for some work. I'd start there
Make sure you check him out Holmes Auto Repair - 16 Nashua Rd. Pepperell, Ma 01463 - (978) 433-0400 - Home
Ha i have actually checked that place out before... all these places are really close by actually. Too bad im not in mass for another year or so...