When determining "left rear", are you using the fan/crank pulley end of the engine to reference "FRONT"? If so, you are correct.
There may also be a possibility that the block heater will not fit a "Stage II" H-20 if it was designated (by Zero Start) to fit the older H-20.
At this point I would suggest that you try to get in touch with the tech dept. at Zero Start if another member can't furnish better info.
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