The sure grip carriers are interchangeable from case to case. I have run a clutch sure grip for years without the roll pin. You just have to know that if you pull the axle the button will probably come out and fall into the housing and you will need to remove the center section to get it back. You can install the buttons into the center section through the axle tube. I have never found it that difficult. The 741 case is just as good as the 489 caee except you have very few new gear ratio choices and is better in that it doesn’t use a crush sleeve.