Hi Purple Pilot:

Here's a couple pictures of a really simple Ryobi motor mount. It's just a flat piece of 1/8" (3mm) aluminum plate cut out to suit. You could mount it on stand-offs, but I chose to bolt it to a plywood fire-wall for rigidity. In the photos, the whole mess is being held on by clamps for a trial fitting.
You may be able to put your hands on a piece of plate easier than the square tube. A bit easier to work with too. I've just used the 4 scews that hold the plastic intake block to the motor, but it may be wise to use slightly longer ones to make uo for the plate thickness.