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Do you hear the fuel pumps engage when you roll the ignition key to On? Should be about a 2 second prime, then they will shut off until you roll the motor.
I mention pumps - the '89s had a low pressure pump in the tank, and a high pressure pump inside the driver-side frame rail about underneath where you put your feet in the floorboard.
When you checked the fuel, was this before or after the filter? Thinking you could have a problem either with a clogged filter, or a clogged pickup screen in the tank.
There's a test port on the fuel rail - it looks a lot like a tire valve. After the fuel pump primes the system before a start - you might want to check this for pressure. If you have a gauge - should get on the order of 30psi, give or take. Either way, watch out - if it's pressurized, it's going to spray all over if you aren't ready for it.
You can check for spark the old-fashioned way - pull a plug, or use a known-good one you have around, hook it up to a plug wire, ground it to the block, and roll the motor. The spark should be towards a bluish color - if it's yellow - may not have enough oomph to fire under compression - perhaps a coil problem, but - one thing at a time.
Suggest to validate fuel flow to the rail, then go from there. Good luck, and keep us posted.
1989 F150 XLT standard-cab shortbed 4x4, 5.0L, AOD, 3.55 gears, manual hubs, 31x10.50 tires, 217K miles. Repainted Oct09.