I have successfully changed mine and I am nowhere’s as adept as many on this site. You need to remove the sound shield. As I recall, much of it is then by feel. And I think an articulating socket handle helps.
I'm late to the game here, but for other it might prove helpful. I bought this for my FV270 and it worked very well. I was able to reach back and change my aft spark plug without removing the back panel. They come in several sizes, so double-check yours.
@toolmaker312 I didn't take the back sound shield off. I just gently pushed it back a little while put that wrench in there and it worked great to remove the plug. I then put my hand in there to start to make sure it wasn't cross threaded and then used the wrench in to tighten. I liked it so much I bought one for the engine
Same as @Formulaben. Don’t recall having to take back panel off. With top and side panels off, you can push the top of the back panel away from the genny enough to get access.
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