hi can anyone tell me how hard it is to do a coil conversion on a 91 escudo (sidekick tracker) 5dr can you buy a kit ?or not and is it worth doing thanx

This should go in the Suzuki Forum, this section is for Builds. 

Are you trying to put them on the front or rear?   What are you trying to accomplish by switching to the coil overs?  Are you doing an axle swap at the same time?

It is always easier to just get some new springs and shocks then to rebuild the suspension, but only you can decide if it's worth it. 

i was just toying with the idea at the moment.my zuk has a 3inch bodylift 3inchcalmini susp lift with the anvil and mod sammy diff with 26spline now. lockers front and rear and crawler box i thought the coil would give me more artic

They certainly can, but you have to build the 4 link system around them.  Lookup information on 3 link and 4 link suspension designs.  You can find quite a few.