hello everyone

hi there.
I am new here. hope you will treat me gently
I have a disco TDi use it everyday to travel work and back and for carrying all my fishing tackle.
What a work horse.
Door locks catches playing up a bit, has anyone else had this problem
Got to fit a new door lock/key barrel ASAP, has anyone fitted a barrel lock?
Are they easy to do
Is there an easy way to fit one

thanks
fishingcoach