Chrysler Repair: 2.7L oil pressure/rattling sounds, oil pressure guage, chrysler dealer

Question
I installed new crank kit, timing kit, oil pump. The oil light comes on. Chrysler dealer switch installed a few months ago.
put a manual oil pressure guage in plug hole on left side of block reads 80psi when started then goes down to 30. under throttle at about 2000rpm oscillates between 60 to 80.
Has a rattling sound up top and up front.  I stopped it after 15 min.
What may be wrong?  Is there a recommended oil pump primming procedure?
Desperate. Please help.
Thanks,
W.K.

Answer
Hi William,
The oil pressure doesn't appear to be out of spec (45-105 at 3,000 rpm at operating temp). The warning light sensor itself may be faulty, or its gray wire shorted to ground so check that out.
I wonder whether the cam/chank timing marks are in alignment with oneanother as the cause of the rattling sounds or perhaps the timing chain tensioner wasn't set up per the instructions in the manual. Are you working with the manual on that aspect of the timing chain as it is rather detailed. What is the year of the car/engine?
Please rate my answer (see below).
Roland