8 3/4 questions

I have two 489 cases both SG, I use the 3.23. for street use and switch to the 3.91 to run at the track. However if you can get the 742 case get it, it's still a strong case. With that being said though I would use the 742 for street and 489 for racing. But if you find a 741 with SG get it. You can take the SG unit out and put it in any of the other cases. But I would only do that if it's the clutch style SG.