being this is an fo2 truck and is almost not a fossil, i would consider checking the distributor shaft for wear. There are a many of these trucks running amuck that are in dire need for new distributors and the point gap can be real tricky to set. If your distributor has no side play you can probably get by with.018 gap. Plugs i would set.035. If you have dist play then pack a lunch and i hope you have plenty of patience.

the unit runs on propane