Hi,
It will be on the lower side of one side of the blower housing. Most common will be the left side as you face the flywheel, but not absolute. Though too large to attach, the manual is here:
http://www.mymowerparts.com/pdf/Kohler_Service_and_Repair_Manuals/Kohler_service_Repair_Manual-K91-thru-K341.pdf
It is over 6 Mb, so it will depend on connection speeds.
Peace,
Clarke