well I dropped my rear drive shaft off to get re balanced and put a new rear knuckle on, while its there I was thinking about having them lengthen it a bit too. Is that a good idea? and if so how much should I tell them to lengthen it. I have a 4 inch lift without a sye, but I do plan on lowering the transfer case. If i do get it lengthened i need to tell them today. The jeep is a 96 with the ax-15

thanks