Briggs Opposed twin Starter and Flywheel issues

So i've got a 19.5 hp oppy twin and the flywheel is stuck on there, is there anyway to get the starter off with the flywheels on? Also, with the starter, is the motor of the starter the same as a 12hp(28 cubic inch model)? Can i just swap the gear and nose cone?

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Any help is Appreciated

As long as you don't have really fat fingers, yeah it is possible to remove the starter without the flywheel being removed.  Talks a little time.  That under bolt can be removed with the starter housing once loose.   You can take advantage of the divots under the flywheel if needed. Done it many times.  As for the starter motor.  I could not say if they are the same.

You can get the starter off with the flywheel on. Just need a 1/2” wrench. I think you have to turn the flywheel to a certain spot to make it easier.

There was a ton of different variations between Briggs starters. Most of them mounted to the head the same, the only thing you might run into is the shaft lengths being wrong to put the bendix gear on. You will just have to look them over and try for yourself.