spark plugs 92 f 150 300 4.9 i-6
#3
I agree with the "one at a time" method...also, spend the money and get the magnetized socket wrench with the wobble/extended shaft. Pistons #5 and #6 are a stretch...I actually used 2 more extensions as well...make sure you have a gap tool. The recommended gap should be under your hood...think it's from 0.042 - 0.046...I split the difference and went with 0.044...I'd also recommend that you do the distributor and rotor button too while you're under the hood. I just did mime today...been doing my own tune ups ever since I've been driving. The I-6 is actually easy. Depending on the year of your truck, the #3 and #4 pistons are under the throttle body so you'll probably want to remove the plastic air inlet tubes coming from the air filter. The #5 and #6 pistons are close to the emissions tree and O2 sensor so you might want to disconnect where the tubes and wiring connect when you get to those pistons.
#4
If you mean the easiest way to them, they're right there on the right side of the engine from front to back. It's an old ford you could probably sit in the engine bay to do em haha