I have customers who bought speed kit 3 front and rear to 66 and 70 A body, the feedback I have received is only positive, and I myself have test driven a 70 chevelle, with full setup from DSE and I was very impressed..on handling and smotness.. self on the roads we have here in Norway .. and my customers have not had any problem of any kind when it comes to installing the parts on to there cars.....