Yeah it's the same wt oil that what was in it before I changed it today

 

That sounds about normal at idle,as long as it's not going to zero and hanging there.
About 1/4 between zero and pegged or as you put it between the middle and zero is not unusual for a motor with that may miles on the clock.
As long as it's not dropping down much more when it warms up and it comes up when you raise the rpms a bit I wouldn't be too worried about it.

 

Here's an old thread,seems the oil pressure sending unit switch can be the culprit. https://camaroforums.com/forum/93-02...sure-0-a-6335/