Yeah so the HDMI cable caused me so many problems. I was hoping to use a tiny HDMI ribbon cable but as much as I'd like to say every HDMI cable is them same when it comes to the NUC this just isn't the case. Heres a link to a thread I started on the intel forums to try and get a fix:https://communities.intel.com/thread/103047
Never really narrowed down what the problem was, I think the Intel guys never expected someone to want to use a HDMI cable less than 30cm long so there were interference issues or something. The problem may well have been resolved now but I'm not taking it apart to find out.
Yeah so that's part of the original heatsink that came with the board. It originally has some heat pipes coming off it to a fan at the side of the nuc but seeing as this would have been too wide for my case I removed the pipes put two heatsink blocks on top and the fan right next to it. I don't get any heat problems so it seems to work.
Sorry man I really should have taken more pictures as I went along, it's just when I get started I forget to stop and document the process
While there's still more I can add to it it's realistically not going to get an upgrade for a long time as it's reached the "good enough" threshold for me.