No coils unless original equipment. No Rack and Pinion types. Must have an OEM steering box, may be manual or power assisted. No V6 engines. No overhead valve V8.
Flathead engines can do what they want.
Inline 6 cylinder must run 1 stock factory 2 barrel carb or 2 stock factory 1 barrel carbs. No Automatic transmissions. No coils or coil over leaf designs. Must be leaf spring. Mechanical or electric if electric Shut off switch must be marked.