take the panel off of the inside of the tailgate. My guess is one of the clips holding the rod that opens the nonfunctioning side to the handle mechanism is broken. This literally happened to me last week haha.
the first year Rangers HAD a panel inside the tailgate to access the latch hardware is 1993.
On an '89 what you need to to is take a long blade screwdriver and pry the latch "bolt" (like a house door latch) out of engagement.
you can access the bolt from inside the bed.
After you get the tailgate open you will need a T40 torz driver and you adjust the latch striker (the part on the bed) outwards as far as you can and still allow the tailgate to close
If that doesn't make the disengagement tolerable you can then remove the latch handle (three torx head screws inside the tailgate) and disengage the clips that hold the pull rods to the latch lubricate the latch itself with white lithium grease
(the aerosol kind works best)
And apply a slight bend to the pull rod (you want the rod to be slightly shorter)
Trial and error will get the latch working.
This however assumes that the spot welded in place "end plate" of the tailgate where the latch bolts themselves mount is still attached to the inner and outer panels.
Opening the tailgate and allowing it to FALL to the end of the cables can break those end panels out of the tailgate making it seem like a "latch" issue when it is ingfact the tailgate itself is broken due to user malfunction.
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