They would be quite restrictive when cooking. This is why I designed an old chimney as a pantry..... however you could go with a wall ovens, microwave, etc. type of fit out rather than a freestanding cooker. Have the cooktop and range elsewhere.

is there any space to lower the floor without compromising new flooring or height of cooker or could you have an oven in a different location and install only the cooktop in the chimney? ...years ago we were able to install an industrial strength exhaust fan inside a chimney without a range hood but discuss with your electrician before assuming modern standards ... i would prefer the cooker in a different location as the chimney is uncomfortable to work at, difficult to clean and install electrical wiring and subject to invasion by possums

Thanks for your comments. Unfortunately it’s the only place I can put the oven so I’m stuck with that.

then enlarging the opening to allow space for the clearance and a range hood would be the most complicated but safest option (NB keep in mind new flooring height as well) ..best of luck with your choices

I’ve pulled out two similar chimneys. I love preserving original features but sometimes the compromises are too great. If it doesn’t have a full chimney external to the roof ie just a metal vent, it is relatively easy to pull down.

Remove the whole lot

congratulations, well worth all the effort, well done!!

Wow, that does look amazing.

Love it so worth keeping