The seats will go 'backwards' fairly easily. 99/00 had a passenger side occupancy sensor, 01/02 had a different occupancy sensor. The 96-98 have neither, so you can use all 3rd gen seats. Assuming non-powered, of course...
I put '97 seats in my '99, but moved the occupancy sensor over from my '99 seats to the '97 seats...
While you are at it swap the seat bottoms left to right (you can swap the seatback foam too, but you have to keep the upholstery on the correct side if you have lumbar adjusters) - the passenger seat always has less wear...
-Charlie
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'99 4Runner SR5 Auto -
4WD swapped
'89 Camry Alltrac LE 3S-GTE 5spd
'17 Chevy Volt Premier
'16 Honda Odyssey Elite
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