Uzi site disassemble

[getnany]

I am looking to change the spring that keeps the pressure against the barrel nut. Is there a special tool I need to disassemble the site to get to it?
Any help would be appreciated
Thank You

 

[MGMAN45]

Remove top cover, look under front sight .That's the catch.Take flat blade screwdriver, apply downward pressure on rear of catch and push forward catch will come out.Replace spring or catch or both. Remove the barrel first.LOL