[DeTomaso] intermittent spark...

[JDeRyke at aol.com]

Most electronic devices either work or fail completely- ew partially fail. 
Ford put out a Duraspark troubleshooting brochure 20 years ago, but in my 
experience I've never seen the distributor pickup cause a problem; it's always 
the brainbox and it either works or is forever dead. 
Have you looked at your ignition switch? After 42 years, we're getting 
quite a few semi-failures on the electric part of the switch as well as 
mechanical binding-up. The electric part of the switch separates in the car from the 
mechanical part via screws without drilling. Good luck- J Deryke