Sorry for the frustration! I'll try to post some pertinent information. I take multiple pics of repairs performed, probably too many, primarily prior to alterations.
John Deere 68 Riding Mower (8HP B&S) - original engine
A684E
053897M
Briggs and Stratton
191702 5632 01
79082712
Repowering Briggs and Stratton 8HP
193702 0215 01
90100830
The original engine had electric 12v starter, flywheel with ring gear, but no solenoid or alternator. Has plug in for external charger. Two safety switches, trans. neutral and brake, so engine cannot be started in gear or without park brake. Uses 4 post turn key ignition switch and pull switch for kill.
The replacement engine has electric 12v starter, flywheel with ring gear/alternator internal magnets. Adding solenoid, standard 5 post ignition switch to start, kill, utilizing magneto and ground terminials to kill, battery and solenoid terminals to start. Had not planned on adding voltage regulator, since mower likely not run long enough to over charge battery.
Hope this explains things better!