@Jmellc -
Not sure whether or not you've solved your problem, but I am a bit confused.
The only 15/16" socket required for most any walk-behind lawnmower is for the flywheel nut on a Briggs & Stratton engine.
You may or may not need an impact to remove that nut.
If you are removing the
blade bolt at the bottom (drive) end of the crankshaft, you should be dealing with a 9/16" or 5/8" bolt head, not 15/16".
In either case, the bolt (or nut) may be rusted or galled, in which case you need to pony up for a can of good penetrating oil, douse it good, and go back in the house for a day or two and let the oil do its magic, then hit it with the blue wrench/cheater bar/impact gun as necessary.
I have found that a 120-volt "Bauer" 1/2" drive impact gun works wonders.