Expansion Tank Hose
 

Can anyone advise as to how the connection near the expansion tank fill cap (to the right) for the vent hose comes off? I pulled the clip out but for the life of me I cannot get it to slide off

There is a black locking pin that you already pulled up, that should disconnect it. If not, coolant seized the fitting on there. Give it a slight twist. There are guiding rails that wont allow you to twist the fitting very much, but just enough to break the seal and just pull straight out.

It took me an hour to persuade that fitting off.....

That sucker must have been seized good on there. You changing out that hose too? Might as well. Chances are you put that fitting back on, its going to leak.

The "plastic" portion of the hose broke (more like snapped) over the weekend. I just purchased an entire new hose to reinstall.