The late build 04s don't have the same HPOP that the 05 and up trucks do. These have the same top discharge HPOP that the 03s have but they share the "wavy" high pressure oil rails with the later engines. These seemingly "hodge podge" changes can be confusing if you aren't familiar with the different "flavours" of the 6.0.

Also -
On 9/29/03, the high-pressure oil rail was redesigned (wavy design) to increase oil capacity and to reduce noise. The new design wavy high-pressure rail has increased the volume from 15 cubic inches to 30 cubic inches. This reduces pressure fall-off during injection and improved emissions and fuel economy.
• The stand pipes’ serviceability has been improved.

Also as an FYI -

From the beginning of production, the high pressure pump cover retains a sleeve which provides a sealing surface for the o-ring on the high-pressure oil discharge tube.Mid-way through 2003 MY, the sleeve in the high-pressure pump cover was removed. • The sealing surface for the high-pressure oil discharge tube is now totally machined for the o-ring seal.