SoWeezy wrote:
It needs securing to the wall at the top to stop it moving: have you done
that? Usually some small L-shaped brackets.

there's no way of fixing anything to the bath, unless there's a specific
clip/bracket for the job that clips under the lip and is screwed to the wall
?

I could drill through the lip and screw it to the wall that way but don't
want to take the risk of ruining the bath (SWiMBO would kill me (c; )

TBH I've never fitted a metal bath so I'm not sure. Plastic baths
usually come with a concealed timber batten under the lip so you can
screw to that. I'm sure you'll need to fix it there somehow though,
otherwise you'll never get a watertight seal twixt bath and wall.

David