Yeah,Josh is right.The C/30 pickups were 133" wheelbase with a 9' Stepside (GMC Fenderside) bed,except for 68-72 Longhorns (GMC Custom Campers) which are wide beds.It sounds like yours has an 8' swapped on it.There`s never a shortage of people telling you facts as they see them as if they are actually true.That`s why we`re here,to set the facts straight.