What makes you think it will be the same? Oil pressure isn't the same throughout the entire engine.
I put several gauges on my engine and the results were shocking to say the least. For example, you can have 80 pounds on the gauge and damn near nothing at the rocker shafts.
The length of the tube or gallery, the number of 90's, the surface finish of the tube all change the pressure in the tube.
So, thinking it through IF you pull oil from the filter or the back of the engine, run it to the front and then add some 90's or whatever to get the oil to the front you will have different pressure in that tube.
