The message
from "IAN CAPEL" contains these words:

Its a straight pan connector and it is as simple as taking the pan out
pushing on the connector and replacing the pan as long as the pan oulet and
the soil pipe are level with each other.

You might also need a new cisternpan coupler, they sometimes pack up if
disturbed. Also, have a couple of long brass or stainless screws handy
'cos the ones holding the pan to the floor may be rather corroded,
depending on how good the aim of small boys in your house has been over
the years.

--
Skipweasel
Pay no attention to that man behind the curtain.