I have a 1979 Monte Carlo and I have 10 switch a ride set up. The rear bags are firestone 2500, I was wanting to swap those out with some universal bags that have an 11" stroke. My question is if I go with these bags to give me more lift in the rear will I need extended shocks. With this have any effect on the drive line? Would it be a straight swap on the bags and the shocks or would I need to do any type of modifications? Thanks in advance!