Exmark Lazer new motor

Hey guys I have a 2000 Exmark Lazer with a Kohler pro command 26 in it, it has two broken rods and is pretty well shot case is good but that's about it, anyways thinking about putting a new motor in it, wanting to do away with the EFI and want to just keep it simple and put a carbureted motor in it, sence this is a "retired" motor wasent sure what my best bet would be, maybe I could put a Kawasaki in it, any advice helps thanks in advanced

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Exmark Lazer new motor