Please help!! no oil pressure after oil change!!

Ok thanks!
It's not metal parts, they are far to light but I don't know were they are coming from but I have a feeling that's some old stuff that have been there for a while.
I've ordered a new pickup, oil pump and the prime tool, I'm going to remove the old pump and try to push the drive shaft from the pump side instead of trying to pull it out from the dist. side and then prime the new pump before starting the engine, hope it will work then.
So much trouble for a simple oil change...