I just seen one of them big sixes like in that picture
http://img512.imageshack.us/my.php?image=77sixpt8.jpg
Its sitting in a barn here in Arkansas. The dude put a V-8 in the truck. It is maybe a 54 Dodge with 3 back windows. One in the middle and a curved window on each back corner of the cab.

250 Integrated Head / 1981 C-10 Pick up.