Instructions needed for replacing heater core hose assembly?

To be clear you need the heater hoses to be replaced not he heater core, correct? There is a big difference FYI.

Here is a repair guide to help you step by step for the heat hoses:

https://www.2carpros.com/articles/replace-heater-hoses

Check out the images (below).

Correct, I replaced the heater core around a year ago. But recently a leak developed on one of the hoses calling out of the heater core so I'm replacing the heater core hose assembly. On the driver's side the hose runs behind something that looks almost like a leaf blower attachment. It's black plastic, how do I remove that? My very crude drawing shows the location.

So you see the regular hose clamps and the crimp style of hose clamp? These you can't replace. I have seen people use a hack saw and cut them off and use regulator hose clamps, but it can be a little difficult. Other than that, you can use regular heater hose and a hose tee to help build your own if you can find a replacement.

I have the replacement part already. But the old one I'm removing travels behind some hollow black hard plastic thing that looks kind of like the plastic on a leaf blower. I can't get that black plastic piece off. It's on the driver's side right below the windshield wipers.

Can you upload an image of it?

Yeah I'll get a photo and upload it. I believe it has something to do with the windshield wiper motor as it's directly below it.

Sometimes these hoses can be difficult to get to and you may need to remove some items to get to them, but we will know more once you upload the image.