iv been diggin and not found anything, my mechanic has a msd 6a on his dart and said he will sale it. but my question is will it work on my sbc considering its on a mopar. if so what would i have to do to hook the box to a gm hei?

 

There's very little inside an MSD box. A 6A just has a basic ignition module inside. A 6AL has a high end rev limiter added to it.

The ignition module doesn't care what kind of car you have. Download the instruction manual from MSD to figure out how to hook it up to different types of cars.