I am putting a 4in BDS lift on my 72 Jimmy and am planning on using Rancho 9000 series shocks. I currently am using 9000 series shocks. The Rancho application guide says with a 4in lift I should be using a 9001 in the front. At compression it is 13.25 in and extended 20.75 in for a travel of 7.5 in. My current rear shocks are a 9008 with a compression of 13.625 in and extended at 27.70 in for a travel of 14.125 in according to the application guide. If the compression length of the recommended 9001's is almost identical to the compression lenght of my current rear shocks, is there any reason to not use my current rear shocks in the front and get 7 more inches of extension on the shock?