Yes pan connector goes inside.Yes I was hoping to replace the existing flush system that has 2 rods from the button to something newer that has the cable attached to the push button..
The pipe on the wall , there is no room for movement really as it looks pretty well stuck firm.. The connector I guess will just slot inside the pipe in the wall and not around it?
No silicone at all.
The one you linked to should do ,however ,measure the length of your existing one compressed ,and also when extended. And ensure the new one has the same adjustable lengths.
You should stick to a flush valve that is operated by the rods ,as you have now .