I also made a rear upper shock x member change, I bought a upper from RMS, that they use with the Street lynx 4 link set up, it is made to go in front of the Diff, I ordered mine without the upper arm welded tabs, turn it around backwards & install it in between the factory x member & it stands the shocks up more vertical. I had to remove my tail pipes for clearance, will have to do some modifications to the pipes , but will run with dumps for now, it is surprisingly quiet without them