low oil pressure:(

[1970 C10 MJW]

I bought an 03 tahoe lt 5.3l flex model in August I put over 10,000 miles on it since then. strangely every time I have changed the oil my pressure has gotten worse until the most recent time its now showing under 10 at regular temp on idle, mind you i have even gone to a heavier weight oil and have changed my oil pump with no change in pressure... I am pretty sure I have a bad main bearing, just want to see what other guys have to say, I am obviously no longer driving it (before you guys ask) I did change the oil pressure sender and I had a buddy with a super fancy computer scanner check the pressure from the obd2 and it confirms dangerously low oil pressure.