Put them on last thing. I put mine on so I wouldn't lose them but then decided to install elbows on the inlets so I could mount the tap higher so it was easier to reach with my gammy shoulder, and dodge that angle stringer on the side sheet that usually gets in the way. Had to soften the Loctite with my soldering iron to get them apart. So the labels probably got a bit of heat too but the fresh Loctite is what really did the damage.
I had to drill out the elbows to the same bore as the inlet barbs too, otherwise there was a considerable restriction to the flow.