Sweep and cleanout help?

[speyguy]

Hi.
I’m starting my third season with my Homestead and have yet to do a sweep. I just pulled the cap and cleaned it and inspected the inside of the pipe with a flash light. Although the cap had a creasote build-up, the inside of the stack looked clean. But, I can not see all the way down. I’m confident I can do this on my own with a little coaching.

My Homestead is a hearth mount set up for a rear exit with a 90* going up the existing masonry chimney. It was a professional install. I have an outside masonry fireplace on the back side of the inside fireplace where the install is. Instead of going up through the metal damper, they went out the back and accessed the flue that way (see photo).

What I’m wondering is, after I do a sweep and push any possible creasote down to the 90* elbow, how do I then clean it all out? I pulled the metal shroud off for the photo and I don’t see any easy way to pull the bottom of the elbow off as it is lodged in with the brick. I was under the impression that this was suppose to be the easiest way to do it. It almost looks like I will have to take the whole back assembly off and pull the stove out to do a cleanout after a sweep????

Also, can anyone recommend an insulation that I can stuff in between the metal shroud piece and the elbow to cut down on the drafts that I get. The fiberglass insulation that I have laying around says not to use it in any applications above 250*?

Thanks in advance!