If you need to put one of those on then you wheel alignment guy needs to be taken out the back... tighed to the towhooks in the rear of your Mu and dragged through the furtherest gorse bushes you can find........
Now on a serious note
You shouldn't need one. They are only a return to center dampener. Your wheel guy should get your truck set right so you get automatic RTC. and if you got wobblely steering its your tires. (Or mechanical like ball joints)
Otherwise its just somthing else to bash on a rock somewhere.
Have a good day...