Guys: I'm really thankful for all the info. Looks like I have found more pieces to my puzzle. The casting number is correct, but since the truck has been pieced from a lot of different years, I don't want to be to enthusiast about it yet. If the block is a 302, and the head is not from that motor, should I still be excited? Can a 54 rear fender be attached to the 55 bed it has now? If you look at the picture, the rear tire is not centered in the fender. On the other number you ask for, I still don't have the truck in my possession, I managed to negotiate the truck in 3 payments, so the guy hasn't given to me yet (haven't give the first payment, just a $150 deposit). I'll try to go tomorrow and check for the info and post later tomorrow. Don't want to, but got to go, I have to work tomorrow (is hard living in a developing country). See you all.
Thanks again.