the 5.0 will fit in the 4cyl. u will need different motor mounts. the car will sit lower in the front cause of the added weight of the bigger motor. just think of it as a lowering springs (lol) but it might feel a little weird. u will need new fuel lines because there on the passengers side of the car in a 5.0 compaired to the drivers side of a 4 cyl. theres a bunch of other stuff too, but i'm not sire of it all.
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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
MY89GT