Water coolant crossover pipe

Cooper S R56 N14 - just spent the last 3 days replacing the water pump & crossover pipe, the job is an absolute PIA ! Much thanks to the Y tube “how too‘s“
especially “project mini,” for anybody else tackling this I found thesee videos the were most helpfull. Despite removal & fitting of the water pump, I found the crossover pipe was a right mare. Something I found not in any videos was “tips” in fitting the cross over pipe into the rear of the water pipe. After 3 attempts at this (1 & 2) both resulted in a leak from a poorly seated O Ring, I ended up using a 34mm o ring (the o ring that came with the oem part got trashed), by dunking the end of the pipe with the o ring attached into HOT water for 2mins then as quick as poss to the car & push it straight into the rear of the water pump....goes in easy, I guess the o ring is cold and solid, by heating....it becomes more pliable?
I really did get pi****d off with fitting the pipe & nearly gave up so hopefully this tip might help another diy owner who is struggling with the cross over pipe. TS