There is an oval shaped hole on the frame near the driver side rear spring hanger. On the driver side it's rusted quite a bit and full of dirt inside, the passenger side looks great. It still appears to be very much intact around the hole, just seems like the hole has rusted and deformed.
Eventually I want to tear down to the frame, clean it, POR it, etc, but that could be quite awhile down the road. How much do you think this weakens the frame? What advice can you offer to help stop it from getting worse? How hard will this be to repair? (I have never welded before)
Here are the pics:
And the passenger side: