To remove the ciggy body, there are 2 x tabs inside that need to prized inwards with a small screwdriver and then it will pop out, and fitting is the reverse without blowing the fuse when pushing the screw driver in like did and have never replaced it to this day. But being non smoker and have never had anything to plug in has not bothered me.
Tip remove the fuse before starting the job!
Nifty