You're making this way more difficult than it needs to be with all the blade turning problems and such. Build yourself a blade blocker or on some mowers a 3 or 4 inch PVC pipe slipped on a blade will block a blade from turning. I'm an old man and sharpen my blades at least 10 times a season without all that equipment you seem to need. I refuse to mow with dull blades.
You're probably right as I usually make things more difficult. Never thought of a PVC pipe to hold the blades and I'm definitely going to try it. Just read that Litrium-ion batteries on the cordless drills only last 2-3 years and would not be a good choice for only using on my mower blades. Thanks,