It may be your starter switch in the steering colum. I have tried to fix this 3 times and it seems to be common issue. I had the ignition rebuilt twice. Power goes in and nothing comes out. On both rebuilds the internals where cooked. The rebuilder said the contacts are very small. When I have starter problems, I hear the click as well. I think it is the L-valve located between the distributor and the AC pump. Nothing to be concerned about.

When my ignition switch started acting up the engine would turn off, or I would lose power to the dash. The electrical system gets really flakey (like some one is flicking the switch off and on).

Detour Racing has great tips. I would start there. If it seems to be your starter switch CONTACT ME! If you know how, it is easy to get out. I had my whole dash and steering colum removed the first time to get it out. Now that I understand it, it takes 2 minutes. Once out it is easy to check it with a meter.