Apologies for there being such large gaps between my postings, but it's silly season at work and I've not had time.
Whilst I've not gotten much done, I have made a slight start on opening up the inside of the builders opening. It's turns out that the brick built gather isn't the original one as the bricks behind it are soot blackened. Thankfully for me this mainly means that they fall out easier! This photo shows the current view up the chimney where I've removed the bricks so far.
The other thing the photo shows is what may be the bottom of the structural gather on the left hand side where there are soot stained bricks. Until my partner's finished child minding for Christmas, I'm unable to pull the face of the chimney apart, so I don't know for sure what I'm finding as yet. But I do know the right hand side is straight forward, and half way down at this point too. Once I can open up the bottom of the opening I expect work to progress much faster. Working through a hole the size of a single block restricts things somewhat!
Oh, on an unrelated note, I've managed to find another complete Record 74 vice, so once I get back out into the garage I can start making plans for my build bench at last!