I needed some brackets for 4.5" angle grinders on the new workbench. They're cheap enough to buy, but I had lots of free 1mm galvanised steel that was saved from the bin. That's even cheaper, and I'm also impatient, so I made some brackets instead. They work well.
ANYWAY that means that I've thought about it and done the measurements so that you don't have to. Mini-instructions in the last pic. Maybe that'll save someone here a little bit of time. :)