[bigblockv6]

[QUOTE=BarryGMC;53349]The 60-66 4x4 frames are completely different than the 67-72 4x4 frames. Different cross members . Springs mounts. Engine mounts. Springs. That's just up front. Peter you don't know what you don't know

You're correct! But it's not What I don't know it's rather what I don't remember and now that my memory is refreshed I do recall the 60-66 K series have more clearance between the engine cross member and oil pan. The 67-72 trucks were a low profile design, my oil pan nearly touches the cross member not allowing the use of the larger series truck 8 quart oil pan.