"A clamp on ammmeter would work, but I hate to spend $80+ for one of those just for this test. I already have a good multimeter, but it isn't the clamp-on type."

Try one of these from Harbor Freight: http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42396

Its harbor freight, so its not the best of the best, but I use mine all the time and it works quite well. Here is my rule for tools.. I buy a cheap one first, and if I wear it out, I buy a high quality expensive one to replace it. If I don't wear it out, that means I don't use it enough to justify the expensive one in the first place!

If you want to use a regular multimeter for current measurement, just disconnect one of the alternator lines and use the leads of the multimeter (connected to the amp reading plugs on the meter) to reconnect the line. IE, the current will go through the meter. Just make sure you have good alligator clips, and be careful.

Peace,
sam