85 vf700 - no spark to the front cylinders.

So I just picked up a nice vf700 that supposedly didnt run. I been tinkering with it and I've got spark to the back 2 cylinders and it will start up and run on the back two cylinders. I swapped the coils and it still does the same thing. So I am assuming its the spark boxes or pulse generator. Does anyone the proper technique to test out the spark boxes and the pulse generator?

thanks,
Micah Shapiro