From tyngsboro you'd be better off going to either Lowell or N Billerica commuter rail the problem is I dont know what the parking situation is.....parking wise the lots fill up fast if you dont get there by 7am sometimes earlier in cases.
there is an AM bus that goes from Tyngsboro to the lowell Transit Center.
Lowell Regional Transit Authority
Lowell Regional Transit - route 10 check it out on the schedule and map.
the problem is the last bus PM from lowell would be 5:30 pm and i doubt he'd be out of Boston by then
Might want to pick him up at the train on the way back at N Billerica or Lowell.
All I know is parking is crazy in Boston for commuter rail and not enough spaces. so you have to go early!
If you leave early enough say before 6:00-6:30 every day you might be able to drive down route 3 to 95/128 north and get off a couple exits later at Washington St. - go left off the ramp and cross the highway then go down to the light , turn left at the Kohl's light , then a right onto Commerce way . Follow Commerce Way past the Woburn Mall on your left, and you'll see the red roof inn on your right. Keep going past the Target plaza on your right and then take your next left. you'll come to the anderson regional transit center which has a big parking lot for commuter rail and is relatively cheap to park all day. It would be a better option on the lowell line to leave your car.
(or you could take 495 East to 93 South)and get off at the Commerce Way Exit...(for Anderson Woburn) you'll see target in front of you on the left as you exit . gO straight through the light to the Logan Express/Commuter Rail parking lot , veer right into the parking area. Your first time coming there read the info on the parking machine first so you'll know how to pay and make sure you do it right.
I would say your best bet to get to Anderson/Woburn Commuter rail parking area would be -
495 East - (so you dont get stuck in all the route 3 south traffic) in the Am - then it wouldn't be too long after you get onto 93 south to get to the Anderson-Woburn exit.
Would be prolly 30 min max. +/- traffic. then you hop on the commuter rail and are on your way.
In the coming years there will be a new train station built at Spit Brook Road in Southern NH (Nashua) which would be easier for you and
I think Tyngsboro might even get a commuter rail station or at least N Chelmsford which also might be easier, but nothing built yet,.
Anyway Anderson-Woburn Commuter rail is my suggestion
--jeff
Winchester, MA