Your factory oil pressure gauge is nothing more than an idiot stick. When the sensor detects 7psi, it closes, telling your gauge to move....somewhere into the "normal" range. THAT IS IT!!!
It will not move as pressure increases or decreases. I took my factory lead off and simply grounded it to the block, oil pressure gauge reads in the middle of the "normal" section now.
I went ahead and installed a VDO mechanical oil pressure gauge, electrical coolant temp gauge and a double pod where the ash tray once was. These are right on the shelf at Napa. Sleeve the oil pressure capillary tube with vacuum tubing to straighten it out and give it abrasion resistance. If this little line breaks, you will lose all of your oil.
The aftermarket gauges are such a huge difference I can not even describe it. What a peace of mind it is to know what your engine is doing at any exact moment. How many degrees is it when the gauge reads "R" on the "Normal" scale anyway?
Cut me a break
Sorry for the rant, I am not trying to look down on anybody, just releasing frustration as to Ford's inability to deliver good gauges. Do yourself a favor, get the aftermarket gauges and don't look back