As long as it is a 6' bed it will work.  The bed mounts are basically located in the same place, however they aren't exact.  The '79 bed I put on my Dad's '86 farm truck left a gap of about an 1" between the cab and bed. 


Gap from a distance.


I wanted to pull the bed off and elongate the holes to reduce the gap, but my Dad said he didn't care, so we left the bed as it sat..