I just got finished installing a Muncie 4 speed in my 66 basket case GTO, and while digging thru the pile of parts that came with the car, I came up with 2 crossmembers, which up to this point I thought were the same for 64 -67 manual or automatics. One, has the usual raised stamped lip across the front and the back, which always fills up with dirt, rocks and grease, while the other had the same lip across the front, but on the DS rear the lip was flattened and opened, almost like a drain. I know the one with the flattened area came from a silver/red 67 4 speed goat, no idea what year the other is from. Any thoughts?