2001 Rancher 350 charging issue

Hello Everyone.
I am working in Barrow Alaska and someone gave me a Rancher to fix for them. In exchange I can use it for my stay here in Alaska. It came with a new batter and a few other parts. I have been research the forum for my answers. And it has been a great source for me. I am sure I know the answer already, but I want to make sure before I give up.

My battery holds a charge. And it the quad will run for days before the battery is dead. But it does die. And I know its coming because the dash goes out first. Then the rams get low and it will only idle. Then eventually it dies while running. I assumed it is the stator. I was all prepared to replace it. I have done it before on many bikes. But when I saw what must be done on the Rancher, I got sick. There is no way I can pull the motor here. I don’t have tools or the time. There are just too many things that could go wrong. And on the tundras nothing is easy.

All that being said, And I am sure I lost most of you. I went out to look at what was involved with taking the stator out and found the rectifier unplugged. So I plugged back in and thought GREAT. Its not the stator. But when I started the bike, the battery level still dropped as the motor ran. So finally my question. Could it be anything easier or cheaper other then the stator? Could it be the rectifier? I know it was disconnected. The plug was swinging loose. Now that its plugged in it seems the same. But the battery is low around 7 volts. I am charging it up now. Can I hope now that the rectifier is plugged in things will be better? Or should I still expect to do the stator? And advice(no guesses please) would be great. Thanks