Kitchen sink overflow help please

[speedyhide]

hi - my kitchen overflow is leaking and I’ve discovered the connection has come loose but there is no space to get my hand up at the back to reconnect it. Is this a simple reconnection job or should it be fixed better. I’ve circled in red the two points I need to connect.
Unfortunately the access hole is too small. Has anyone got any advice on reconnecting?

Thanks, Matt

 

[ShaunCorbs]

Just push it back up onto it

There never 100% solid for my liking

 

[Ben-gee]

Cut away a bit more of the chipboard unit if you have to, yes I know it’s tight - but not impossible.

 

[DjClubber]

Or completely remove overflow, reconnect then align and fasten back in. The overflow is screwed in from the Sink End. Maybe add Silicone then push back in and let set for a better connection, also the same on the back prior to connection giving a sound joint. Hope this helps.