i need to know how to put back a part?

my printer stopped working and the ink light remained on all the time, I reinstalled it, changed the cartridges amongst other basic things like cleaning the nozzles etc, however there is a sort of rest for te cartridges and where the ink pipe connects, this consists of two pieces that somehow slot together then replaced into the printer. Can anyone tell me how to put this part back in as I have not got a clue and when I spoke to a "printer repairer" he told me I ay as well just buy a new printer. By the way it is an Epson RX425