Help plese - oil pump issues

[308commodore]

Hey guy's, missushas a nissan patrol with a factory fitted rb30 , 5 speed. I know it's not a holden but give a guy a break. lol. car has got 196000ks on the clock. Lately been noticing a ticking noise on start up. Oil gauge in the car ranges from 0 - 6 i think. We're lucky for it to get to 1and1/2. Had a full service at 190000ks. I'm thinking maybe a oil pump on the way out. If need be i can hook up an aftermarket oil pressure gauge to the motor to get an exact reading. If so where do i plug the oil line into for the gauge? If it is the oil pump what's involved in removing and replacing pump with a new one. I really appreciate anyone's help with the matter.
cheers ray...

[jatsvl]

the oil pressure sender unit is near the oil filter (large bolt looking thing with 1 wire attached to the end) remove that and attach your oil gauge,
other possible causes are low oil, thinned oil and worn or clogged lifters.