I want to drop the rear only of my 05 SCAB with a short bed. The wheelbase is very close to the reg cab with standard bed. I have my shackles and was considering installing them when I read an article about shimming the rear axle to compensate for the different angle. Supposedly there is a chance that the driveshaft may cause a vibration without shims. I was wondering if the long wheelbase trucks are more prone to the driveshaft vibrations or is the shorter wheelbase trucks more prone to driveshaft vibrations.?