Would it be quicker to check the battery by taking it to a shop and having them do a load test? It might be a free test.

 

From what I've seen, the load test that they do in typical auto parts places won't necessarily detect the slow leakdown condition.

 

Xstrange (by the way, do you have a first name?) is it possible that bad diodes or something else in an alternator can cause a slow drain? I have a seven-day-go-dead top line battery in my '67 and have resorted to the pull the cable fix at the airport.
I have an ammeter that has a 300ma top scale but I am afraid of putting it in series with the battery cable in fear of blowing it out it my drain is too high.

 

I had an aftermarket oil pressure gauge that hooks straight into a fuse and it was hooked into the wrong one so it was on constantly.