Can't the alternator be tested using a volt meter and putting the red lead to the big black/red wire and connector on the alt..
Then grounding the other end to the frame or something ?
I know my battery's are bad but I'm trying to check the alt..

 

Yes if you want to check voltage out put of the alternator, you can either touch the red lead to the large lead on the alternator and the other to battery ground or just connect red to battery positive and black to battery negative. That will just give you a voltage out put but will tell you nothing on the amp output. If you can drive it, just about any auto parts store will check it for you free.

 

DITTO. And if you can't drive it, our alternators are easy enough to pull out. A lot of auto parts stores have a machine they will put it on to test it.