LOOK MUM NO COMPUTER has a great set of video about removing an organ from a home, and setting it up/modifying it in his place. I highly recommend. https://www.youtube.com/watch?v=8PwwRR8deHk
Yeah, that's great. In [1], you can see it (Joan's organ) in its original state. If you follow the youtube playlist, you can see the amount of work it took to get it out and install it. That organ has some 15 stops, many of which are "borrowed" (i.e., the 4" uses the same pipes as the 8", but plays an octave higher), and it doesn't have much wind pressure. So it is small. The organ from the link has 117 ranks, and its pipes extend far beyond Joan's organ, and it fills a hall instead of a small parish, so it is huge. Multiply the work done by Sam Battle (who's behind look mum no computer) by a factor ... 40?
I deeply love this Youtube channel, and I have been following his organ saga for quite a while! The initial move/reinstallation was super enlightening to understand how organs actually work.
It's worth noting that this project is installed in his museum of old technology called THIS MUSEUM IS NOT OBSOLETE [1]. Tickets are £5, and under 13’s are £3.
I've never been to Britain, so I can't attest to it, but it seems like a cool place if you like retro technology.
[1] https://metro.co.uk/2021/03/09/house-with-full-organ-built-i...