Pete and Sparks.
Nothing that complicated. Just scrap plywood doubled up to obtain the required spacing I needed.
Actually the plywood is Russian Birch. I have also seen it labelled as Baltic Birch.
It is metric measured and comes in around 18mm thick and 13 layers. Not quite 3/4".
The plywood is just some scrap pieces I had left over from when I built my folding field assembly stand. I picked up the Baltic birch plywood from the local Home Depot. Smaller sheets than the 4'x8' were available.
I am surprised no one has made a comment about the deck screws to hold the motor to the standoffs.
I do know the screws and standoffs work as I am using a similar setup in a 6s lipo system and have never had an issue.
I will post some more pics of the mount tomorrow.