MSD

You need to see if the MSD box is the problem.

It is very simple:
- leave the thick red & black wires connected to the battery
- disconnect all other wires.
- check for voltage on the thin red wire. If it has voltage, the box is defective.

A cheap fix, cheaper than a new box, with rev limiter:
- Cheap HEI dist [ Chinese, they work well ]
- MSD # 83647 4 pin module [ this mod has an adj rev limiter, mounts in place of existing module ]