i don't believe the 89 panel will fit on a 91. the 90 has air bags and the bottom of the gauges has a different shape to fit around the steering wheel. also the 89 has the tach on the left and speedo on the right. 90-93 have the tach on the right and speedo on the left. unless u tear the whole thing apart and just use the motor and put it back together properly it might work.
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89 GT AOD w/ shift kit, B&M rachet shifter, Trickflow intake, Crane (E-type) cam, 70Tb, 75MAF, 1.6 Rockers, Pulleys, MAC headers and H-pipe, Dynomax mufflers, K&N, 3 core radiator, white face gauges, custom interior, cobra R rims. 14.9 at 95.07mph with stock 2.73's.
89LX 2.3 Notch, daily beater!
MY89GT