The 88400 is suppose to be a direct fit for the comet/falcon setup. Most people don't have a single problem at all. However, I did. Mine would not fit on the drivers side because of the z bar linkage set up. The guy that installed them modified the header tubes so that they would fit. No big deal really. If I remember correctly maybe the 88400 are for an automatic trans, Not a manual. I really can't remember, But you shouldn't have any problems.