afaik the parts are interchangeable for the same body styles, 73 to 80. 81 to 87. The cut off was when they changed from having a cowl to a full length hood. I have managed to put a new style front end (86) on an older truck (78) but it was a pain.. the major differences will be if you have single or dual headlights. are the turn signals in the bumper or in the grill etc.