GM 4pin HEI run problem..starts..but won't stay running

Found the problem. The pigtail at the Igntion switch was very loose. Slid back somehow. I'm surprised it would even start.
This would have been very bad . Had I been driving down the road (possible wreck).
Going to try to crimp the wires in the pigtail to prevent this from happening again.
Thanks for all your help. :)