After a little research, I realized that the rubber seal that goes under the wing nut holding the lid on the reservoir was blocking a small hole put there to relieve pressure. Hoping that's the case, I pulled the pump off, verified that it was leaking from the front seal, and went out and bought a new seal and a couple of o-rings for under the reservoir. And I cut a little bit out of that seal to let the lid vent.
The most time today was spent cleaning up the reservoir and pulley for paint--I figured while I had it out I'd paint it black.
I'm not going to say it is fixed yet--we'll have to see. Fingers crossed though.
I also replaced my beat up old parking brake handle with a new old stock one. The grip portion of the handle requires paint, so I sprayed it silver to match the column and dash, and installed it. It is nice to have a parking brake again.