I just fired up the new motor ( used 01 for my 98 ) and after a couple tries to set the dist properly it fired up and was kinda rough and the oil pressure gauge never moved. I turned off and repeated a few times running it barely at all to see if any change but no avail. I dont mind if the gauge doesnt work but no pressure would make this engine like my last one.....garbage. What should I do? I used the sender from the new motor ( i assume this piece in the back of the motor is the sender ) and the gauge worked with the old engine in. Please help!!!

 

I'll assume that it is plugged in. You could try swapping the senders, but between the removal of the sender that is currently on there and the old one, you should hook up a manual pressure gauge to assess the oil pressure.