When my mechanic worked on the exhaust I asked him to check over the rest of the truck and I explained to him what it was doing and what I had replaced. He said everything I replaced is known to be a common problem. As far as the removal of the catalytic converter and running the exhaust straight back just behind the cab with the Super 10 muffler he said that was the best thing I could have ever done. He did replace the 02 sensor as well. He drove it twice in 2 days once around 20 miles and the next day around 50 miles. Said it was one of the best running trucks of that Era that he has ever driven. Maybe we got her fixed.