Opening up fireplace, how to remove a section of clay liner?

[saladdays]

Dear All,

I'm planning to open up my fireplace and then get an HETAS engineer to install the stove.

This is my fireplace:
View media item 61634
Looking up and left:
View media item 61635
Looking straight up, yes that's my forehead:
View media item 61636
The builder's opening supports the corbelling which supports the flue. The height from concrete hearth to flue is about 965mm, 38" which doesn't doesn't leave enough space for the stainless steel liner, stove pipe and register plate.

I need to know how to remove the first piece of clay liner. It's a 45 degree bend. What steps do I take? If I remove the corbelling will it all come down?! Will it hold itself up?

Thanks for reading.

 

[Norcon]

I did my own recently and just went in from underneath.
Yes it did cross my mind that the entire flue system might end up in a pile at the bottom given it was filled around with loose rubble.

I'm a chancer though when it comes to diy.

Some images here.....
//www.diynot.com/forums/buildi...-adding-lintel-for-log-burner.333172/#2763334

With poured concrete you end up with a flat surface of concrete to bolt a gasketed steel plate against.
This steel plate will incorporate a compression joint of my own design to seal the gases.

I'd remove that nice hearth before commencing any break out.