In a bid to try and sort some space I thought I would get the computer up on the wall. This might be of use to someone out there. :-)
The mess to be dealt with ...
Slowly winning on that front and making room for next steps.
Stage 1: Cut out some 6mm steel flat and shaped to this triangle. Front plate is clearance hole drilled 6.5mm and the back plate is tapped M6. With three M6 cap screws in place this is should be able to clamp on like a "really strong clampy thing" (alternative phrases failed the census checks)
Hand holding the vertical bracket before welding.
The result all welded up and on the wall. Clamped good and solid as well. The bracket is also painted with rust preventing black paint.
Ta da! Success. With some bench space reclaimed!