Long, long ago in a far, far distant galaxy. Whooops, wrong story. LOL
Any way do some checking before you spend big bucks on something that you may not need. When I was in the Army in "64", long, long ago, we had 2 1/2 ton trucks with 302 Jimmys in them with 24 volt systems. The 24's turned over no better than a 12, just longer, witch was needed because the crap wouldn't start on a good day. We also had 5 ton semi's with 205 Mack Diesels with 24 volt starters. They also wouldn't turn any better than 12 volt. Some over the road trucks used 24 volt starters with 4 six volt battery's and a device called a series-parallel switch. They weren't any better than 12 volts and a lot more complicated wiring. I don't think any are in use today, at least on new trucks.
The 168 tooth flex plate will give more reduction to turn the crank.
Just some more to confuse you in your quest.
Ron