Observe the manual, single digit pressure numbers with warm oil ar considered common. Also the autometer pressure gauge isn't the most reliable nor accurate, if you have the brass style plunger sender unit.

 

I installed a Defi BF oil pressure gauge a few weeks ago. I mounted the sender down by the filter so I'd get the "higher" readings. Here's what I see:

Cold start - 80-85psi right off the bat, then will lower as it warms up
Cruising - in 5th gear cruising at about 60mph, I'm roughly at 60psi or so. It's funny, in 5th gear the oil psi will roughly match the speed I'm going (to a point...)
WOT - 110psi or so
Idle - 18psi

 

I have the electrical Defi D series oil pressure gauge tapped into one of the gallies above the oil filter. When the car is warm the oil pressure dances between 15-20 psi (because of the lope in idle) and at 80mph in 5th it will read ~85psi. If I remember correctly, the oil light in the instrument cluster will not come on unless the pressure drops below 4 psi at idle.

 

Sounds like we're on par with eachother for Defi...good to know