Is my alternator failing?

Could be. I'd just pop it off and go have it bench tested. Most large chain auto stores will do that for you for free.

Also, after buying my Dart, I read some of the posts on doing the amp meter wiring. Looking at the system and the potential problems I went ahead and did the modification. Glad I did. I'll probably put a volt meter out under the bonnet somewhere just to keep an eye on things, but feel better at not having such a problem area still hooked up.

Cheers