My 1985 Ford Bronco 2 is having occasional issues
A failed started does not always give us the tell tale click or thunk sounds. This is where i would begin.
It would take about 15 minutes to pull it out, after that take it to a parts store that offers free testing of these components and you will have your answer.
From what you have told me I am 99% certain this is your problem, since you have lights coming on, you can eliminate the possibility of a bad battery and since the battery is good the alternator must be as well.
A fuel issue wouldn't come into the equation when the starter is failing to engage.
Start here, if the starter tests out as good, which I'm fairly confident it won't. The next thing you have to look at is where the motor is locked up. While the starter is off the truck, use a heavy screwdriver to try to turn the torque converter, it should be very hard to move, but should move with some force, if it doesn't, the motor is a dead duck.
But as i mentioned, I'm fairly certain it is a starter issue. But if this is not the case, feel free to come on back and we can take it from there.
Thanks for using FixYa, and Good Luck.