I bought a 1979 Trans Am with the Pontiac 400 engine from someone who lived in Santa Barbara County, which at the time did not require the bi-annual smog test. The owner had bought the Trans Am for his son, who had removed the converter and put in a dual exhaust system. Fortunately, the son had kept the converter and the owner reimbursed me for the cost to buy a replacement exhaust system, which I bought from Sears and was manufactured by Arvin. I put the Trans Am on ramps and got out my hacksaw and replaced the exhaust system, which fit perfectly. Years later, I did have to replace the original converter as it got to the point where the Trans Am wasn't going to pass the smog test.