1974 Ford Pinto Remember points and ignition coils

1974 Ford Pinto 4 cyl

I own a carpet cleaning business and my machines utilize old Ford 1600 cc 4 cylinder Pinto motors anywhere from '72 to '74.
I was doing some adjustments on one today and touched up against the ignition coil and found it extremely hot. This is on motor that was cold and ran for less than a couple of minutes. Coil was just replaced and the distributor wire running to negative side of coil.
Thanks for all your help.