1958 Ford 861 Tractor

If you hook the positive cable to the solenoid, it either always was negative ground or was converted. Much better for you either way. I have an article that makes it very simple to understand how a point system works and has diagrams that make it very easy. PM me your email address and I will send them to you. It will help you determine what is happening to the spark. Here are some basic points pasted from the article.

The circuit that powers the ignition system is simple and straight forward. (see above) When you insert the key in the ignition switch and turn the key to the Run position, you are sending current from the battery through a wire directly to the positive (+) side of the ignition coil.

The points are made up of a fixed contact point that is fastened to a plate inside the distributor, and a movable contact point mounted on the end of a spring loaded arm.. The movable point rides on a 4,6, or 8 lobe cam (depending on the number of cylinders in the engine) that is mounted on a rotating shaft inside the distributor. This distributor cam rotates in time with the engine, making one complete revolution for every two revolutions of the engine. As it rotates, the cam pushes the points open and closed. Every time the points open, the flow of current is interrupted through the coil, thereby collapsing the magnetic field and releasing a high voltage surge through the secondary coil windings. This voltage surge goes out the top of the coil and through the high-tension coil wire.

This is the very basics. Do you have power at the coil when the ignition switch is on? Are your points properly gapped? Are you getting spark at the coil and not the plugs? All easy to check. I'd be happy to send you the article. I know about point systems and I thought it made it even easier to understand.