Quick update on this. I removed the whole lot a few weeks ago and it all went swimmingly. Bloody hard work for a newb, but that's to be expected. I did the removal with the tools I had so it took me a good 30 mins to cut through the flow and return pipes. I've since had a brickie mate come round and brick out the whole thing in imperial bricks and it looks great. Next step is to get a plasterer round (next week) to finish the whole thing off, then I'll post some pics up of the whole process. Thanks everyone.