Irv,
According to the 2001 owner's manual: "The front headrests are not intended to be removed by the vehicle owner in normal use" "The headrest can be removed by dealership for service".
However, in the 1999 Isuzu SUV Reference Book the headrests can be removed after they are pulled up fully to expose the two push points under the headrest pins(they are located in the front of the seats as they are facing the dash)
Good luck and don't break anything.....John