Necessity is the mother of invention: Using the old chest of draws to support the OSB while cutting out the back-splash:
After turning it the right way up; clamping and adjusting the backsplash and screwing it in place, then mounting the power strip; dragging it into place and leveling it with the adjustable screw-feet, here it is:
Nice.
Necessity is the *father* of invention in this case. IMHO.