Can anyone tell me what the pinion angle should be for a 1/2 ton Chevy pickup with the factory "ladder bar" and coil spring rear suspension?

I'm going to help a friend change his rear end on his '65 Chevy pu. I think the pinion and the driveshaft should be straight, with the only flex being at the u-joint by transmission out-put shaft. However, my friend thinks there is some angle adjusted into the rear u-joint, too. I don't have a shop manual and don't know who is right. We just want to do it right.


Lord, let me live long enough to do all the projects I have planned!