If it's just the upper intake you are swapping it shouldn't be that bad. the biggest pain may be finding 12 point sockets for the bolts.
The procedure from Alldata reads: (they only list the procedure for everything to the lower therefore, some steps are not necessary)
1.Disconnect battery ground cable. Drain cooling system.
2.Remove rocker arm covers.
<~~~Not necessary for just the upper 3.Remove intake duct.
4.Remove distributor. Mark location of distributor on engine and rotor on distributor body.
<~~~May not be necessary for just the upper 5.Disconnect throttle body from upper plenum.
6.Remove radiator hose and radiator fill inlet.
<~~~May not be necessary for just upper 7.Disconnect heater hoses and the pipe to throttle body.
8.Disconnect wiring harness.
<~~~Only applicable to items on the upper 9.Remove heater hoses and disconnect vacuum hoses.
10.Remove brake booster pipe and bracket.
11.Disconnect EGR pipe.
12.Remove upper manifold plenum and gaskets, Fig. 3.
13.Remove intermediate intake manifold and gasket.
<~~~Obviously not necessary 14.Remove lower intake manifold and gaskets.
<~~~Obviously not necessary 15.Reverse procedure to install. Refer to Fig. 3 for torque sequence. Torque lower intake manifold bolts to 19 ft. lbs. Torque intermediate intake manifold bolts to 15 ft. lbs. Torque upper manifold plenum bolts to 19 ft. lbs.
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Fiero's Owned:
1987 Coupe 2.5 5spd May 99 - June 03
1987 GT V6 5spd July 30 2012 - Current
