Sort of yes, sort of no.
The "Option" button on the stock Isuzu remote is meant to run an Isuzu garage door opener, and I don't think anyone has figured out how to link the option button to the rear door popper.
On the other hand a member here, I think it was Raque Thomas, figured out how to rewire the stock remote door lock release to pop the rear door. His final configuration had it so that when you pushed the unlock button on the remote once BOTH doors would unlock, and then when you pushed the unlock button on the remote a second time it would pop the rear door (if you already have a rear door popper installed). I have his instructions printed out at home, but I can't seem to find them right now on the site. I'll keep looking.
Got it - http://www.vehicross.info/forums/sho...21%21%21%21%21
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