Oil Pressure Gauge: This is what I found by checking 2 new style gauges one US made other made in China and 3 old style gauges white and black face all JD part numbers.
New Style: L (6 lbs), M (16 lbs), H (23 lbs)
Old Style: L (6 lbs), M (11 lbs), H (17 lbs) below is old style with JD part numbers
L is 6 lbs M is 11 lbs H is 16 lbs