Rms alterkation track width?

Wish you the best of luck in getting info from Bill. I recently called him and was not very thrilled with him. If somebody were to be writing me a check for 4k I sure as hell would have made sure they were satisfied with my answers.....all I got from him were one word yes and no and the attitude that I was bothering him......that is why I decided to spend my money with Denny......for what it is worth if you look around at Mustang II brake kits you will find that there are a few that alter (narrow) the track width some...perhaps this is how the newer Alter-k's are a bit narrower than the older ones?