I saw this on another forum and was wondering if you really need it or not, I'm getting ready to do a coil spacer lift on my sidekick and now I'm thinking I have to do more fab work, and if so how big does it have to be - I'm putting a 2" spacer in the rear so should I make it the same size?

you shouldn't have to do anything if all your doin is puttin a spacer on.  I have 1.5" spring spacers on my tracker and its fine and iv heard of people putting 2" spacers on with no other modification.  hope this helps

It mainly depends on what shocks you run rather than springs/spacers. If the shocks are capable of more than approx. 2" of extra droop then you will have problems with the stock ball joint binding. It is worth fitting a spacer there anyway to return the angle of the upper arm back to stock, that will help reduce axle tramp.