Both of your drawings seem plausible and should work. Good luck in your creations.

For myself, I ordered the friction drive front mount 2.2 hp Mitsubishi engine kit from David Staton. It is scheduled to arrive tomorrow and be installed over the weekend. That's what I like about friction drive kits. They bolt on in short time. If I had the workspace, I'd love to scratchbuild a motorized engine system.