Not seen anyone do this before.

[BN9Pete]

I have changed hundreds of siphons on low level and close coupled in my long plumbing career, but never seen a close coupled plate under a low level cistern before.

 

[ShaunCorbs]

Used it as a washer hole a bit big ?

 

[BN9Pete]

Used it as a washer hole a bit big ?

No, normal size hole in the LL cistern, I changed the siphon and didn’t have any issues with sealing it, I obviously removed the CC plate.