Ok. That makes more sense then because it was my understanding that the return line was included on the 400s and ac cars. Probably the HO cars as well. Could be in 69 only the 2bbl cars and the base ohc6 cars w/o AC came with no return line. I wonder if all 4bbl cars came with the return line. Ooooooo, that sounds like it makes mine all that much more rare! Probably 1 of only 67,000 or so builds. Lol.