How difficult is it to replace the coupler. We had a plumber install a new one a little over a year ago and I wasn't really watching him but it only took him about 15-20 min to do it. He charged about $140 to do it. And I'm like everyone one else I don't have any "EXTRA" $$. So if I can do it, I'd rather go that way. I can fix a lot of things but this I've never tried. Thank you very much and any and all help will be greatly appreciated I assure you.