No Oil pressure per guage

I am new to this car. I just spent the morning changing the water pump, thermostat, plugs and plug wires. Now according to the gauge I have 0psi oil pressure. I am sure I do have pressure as there is not even a hint of knock. I must have knocked something loose. Where is the sender located that would be causing this???

check around the oil filter screwed into block
what year is car??

97 SE. Need to put that one into my sig. I think what I did was break the sender. I took the PS pump off to get the water pump off and I think when it dropped it broke the sender.

yes its screwed into the block above the oil filter on the sc engine im sure the non-sc is to

New sender unit did the trick. The pressure reading on the gauge is considerably lower than it was before. I am willing to chalk that up to an aftermarket sender vs a GM unit.

Thoughts?

i'd agree some after market parts dont register as good as readings from oem parts
exspecially when talking about guages vs idiot lights