If you look at the picture again you will see it's a doorway type carpet gripper. Not the type you put next to a wall, or even a partition.
Pic 3 shows the cut board going under carpet gripper, which would indicate there being a wall there, this would enable you to carefully prise the short piece of board up without risking any cutting it.
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But you have not learnt enough to get rid of the thermal store!
Or to fit isolating valves so you an play with your soldering!
Tony
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