Jacara,
I am pretty sure that there is a ground wire from the inside of the distributor that goes to the pick up coil. Make sure that is clean and tight. I'm still betting that your problem is the pick up coil, but it could be your regular coil as well.
Try this method.
This is from our friend Blue Beast, (a fellow Bronco owner)
Cryo-diagnostics
If your car doesn't want to start when it is hot and it isn't throwing a code. Or you have intermittant running problems while it's hot and running.
Grab a can of keyboard duster and while wearing protection for your hands, eyes and
other dangley parts, Holding the can upside down, spray for example the TFI module
for about 4-7 seconds and let it cool down and evaporate any condensation on the
outside of the part(2-5 minutes) Then try restarting, If no start still, move onto the next component which would be the pick up coil inside the distributor, So on and so forth moving on to the next component down the line. You will have to alter the spray timing since metal parts conduct heat (and cold) better then a plastic encapsulated part so you may have to add time to certain parts.