I was thinking about doing that but then my truck will sit about 3/4 of an inch lower in the back (63" chevs have a mighty thick overload) and right now it sits pretty level. I was thinking just cutting them to were they are flush with the spring pads on the diff so it would be like they are not even there. 
I did that with another set of springs and destroyed them with heavy flexing and heavy loads. while it seems like a good idea for more flex you might end up with more problems. Not to mention cutting those is a real PIT
even with a good chop saw...ask me how I know....
. My 63's flex very well, even with the overloads, so well in fact that my 31's rub the fender wells in the bed
. I got about 5 inches of lift with my springs and a 2 inch body lift so you have some idea how much that is. I now have a rear axle from an 88 4runner and hope to run 33's soon. So we'll see how that works out. In my opinion the overloads aren't so bad especially if you still use your truck as a truck like I do and will expect to carry a significant amount of weight in it from time to time. Just thought you'd like to hear from someone who's done this. Good luck with your build and nice flex BTW.
