Low oil pressure makes me nervous

My '72 318 motor is old and I'm sure clearances have opened up some. The factory gauges were just refreshed/rebuilt by one of the most reputable classic gauge restorer's and I believe them to be accurate. It is a center sump pan but I made sure the oil level was at least to the full mark before the climb.

The high mileage Castrol 25W-60 is in stock and on the shelf in Mexican Autozones. Keep in mind, the Mexicans don't throw anything away, run their tires down to the cords, and run their cars until they die and can't be resurrected without a saintly miracle. In a desert climate like Baja California Sur (where the Baja 1000 is run) I believe there is a market for this grade of oil.

Part of the reason for my trip is to take home parts for the rebuild of a 340 core I purchased. This will be the last long-range (3000 mile) road trip for this 318 motor.

Anyone want to run/try/experiment with the 25W-60 Castrol high mileage oil can find it here:
Castrol GTX High Mileage SAE 25W-60 Motor Oil 6pk | eBay