Need Headers Installed in Boston

Can't help you with a referral but if you find someone, it's gonna cost big bucks. There's a whole lotta time involved. If the car is a 4 speed some z-bar modification will be required.
If you have a garage, a buddy, and 1 of you can follow instructions, I say go for it.
You won't get it done in a day but you will eventually get it done.
I've done 2 sets now, both A body 4 speeds. It ain't easy or fun but a weekend will get it done
I'll betcha a shop would charge you OVER 500 bucks. Probably way over.