In a 60 look for rust in the rear qtrs and wheel wells, frame also. For a 80, since they are fulltime 4wd check when the front axle service was last done. Also there is an annoying little coolant hose hidden on the back side of the engine that likes to let go and it is a ***** to replace. Try to find if that hose has already been replaced.

For an 80 I would try to find a "soccer mom" truck that never left the pavement and always had routine dealer service. If they don't have the records the dealer can pull them up for you.

I suggest you drive both. The 60s and 80s are night and day different. 80's are more refined than the more utility 60 series.

Let us know what you end up with.