Here's an alternative that another Lextreme member Cobber is using to drive his alternator without the P/S pump, and retaining the tensioner in the stock location. Makes the right side of the motor a bit fatter, however (pics may not be visible to non members of Lextreme.com, so I've provided links to them):
Some have also removed the A/C compressor and put the alternator in that location:
And finally, if you have space in front of the motor, you can reverse mount the alternator, but it makes the motor longer:
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