Thanks guys for confirmation of what I already thought. I am pressing on with the 4.8. I'm sure it will have plenty of power for this rig. I am going back to work on the cab in a little while (hope to get some pics).
1loc10, you were right on the money. The pic with my son is of the 67 and the 68 is pictured below. I get them mixed up. One of these days, both of them will be back on the road.
Here is the 67:
Here is the 68:
