On 12 May 2021 at 20:24:32 BST, "JohnP" wrote:

Annoying situation. My house has locations for 2 wall lights with
architrave boxes for the wiring.

We bought 2 wall lights and annoyingly the the back plate (strip with
turned up ends) is shorter so I can only use one hole. With the stiffness
of the cable, it is difficult to get the wall light flat against the wall.

Have I missed a trick?

You could make some adapter plates to screw inside the architrave box with new
holes for self-tappers where you want them (and hole for the cable!).
Something like 2mm aluminium or 1.2mm stainless should work.

--
Roger Hayter