Sorry i'm not too sure what you mean when you say you aren't getting a positive on the coil side? The coil as you probably know has 2 windings inside, primary and secondary, to test the primary you should probe between the + and - and to test the secondary you should probe between - and the HT connection.

Personally at a rough guess i'd say its the hall effect sensor in the dizzy very common on these cars.

Let me know if u need anymore help.