Seems like those clever peeps in Thailand are onto something:
http://www.btv4x4.com/btv/ref_isuzu-mu.php
http://www.btv4x4.com/btv/ref_isuzu-wizard.php
http://www.btv4x4.com/btv/ref_isuzu-trooper.php
The parts pictured in the second link give more clues.













