Took the regulator in to the shop this morning and it checked out fine -- instant mystery! So, at their recommendation, I hooked everything back up and drove the car to the shop so they could inspect it in situ. Much prodding, testing ensued, verifying that the system wasn't working. Then, after a little more prodding and testing, the regulator magically came back to life. The tech hypothesized a bad connection, but I had wire-brushed all of them. So it's still a mystery but the problem is for the moment solved.

The tech recommended I track down a regulator and keep it on hand should more bad juju crop up. So if you want to sell me your spare, zap me off the list.

Thanks for all the help. If you pass through Birmingham I'll buy you some ribs.

Steve M.