save yourself some parts, and just disconnect the output terminal on the alternator. put your positive lead of a dvom on it. and place the negative one on the engine block. set it to auto range, VDC and light her up!

for best results, increase the rpm some! worst case scenario is you will damage the rectifier in your alternator. Check the ripple pattern before and after this test. This way you will see if you damaged one or more phases of the alternator. Cause otherwise you may believe for the next 20 years that you wernt responsible for the headlights dimming when at idle or the blower fan slowing down, and they never used to.

Have fun!