There isn't much to know; the one side at the flange, is just removing the clamp and the heater core end, requires, you move the lock wire and then you remove it. A jetta I worked on; had the heater core part; stuck on there and the plastic was so brittle, that I carefully cut, broke the pieces off to remove that end. I used a cutting wheel; to put a cut line in the plastic and then helped break off the plastic parts and remove it without breaking the heater core portion, which would be VERY easy to break. You have to be VERY careful; if you do it the way I didi it. This is because the hose coupler end is plastic; as is the heater core end. If you cut or broke the heater core "male" portion, you would have to replace the whole heater core (no fun and allot of work). I did not try any penetrating fluid or something like PB Blaster, Liquid Wrench etc.; doing that, might help but I was under a tight deadline to get the job done and just cut/broke the pieces off. Good luck and take your time, try some penetrant fluid and don't pull too hard on the heater core ends! Or be very careful; if you cut/break off the female part of the quick connect, on the end of the hose. 