The 12an lines and the opening of the rear passages in the back of the block and the elimination of the 90 degree filter mount are to reduce pumping losses. What you are saying is that 5 ft of 12 gauge wire is the same as 15 feet of 12 gauge wire. Not true the 15 ft would have voltage drop. It's your motor, but you are questioning oiling mods by a very successful engine builder that routinely revved over 8,000 reliably. I know you do not like external lines, but they were used for a reason. You do not want that crossover line too big, it offsets the benefit of the front feed line, you want some restriction there.
