I recently damaged my oil pan on my Z6 and a friend gave me his Y8 pan; It went on without issues... but there was a difference though; I'm not sure what you call it but the layer was higher up in the z6 pan, and on the Y8 the layer was flush to the bottom of the pan. I'm running this pan right now, and every now and then on start up the oil light flashes and goes away after idling for a while.... think this could harm the motor?

 

I'm not sure but you may need to run the y8 pickup with the y8n pan...I use a z6 pan on a y7 block but also have a z6 oil pump and pickup.....hope this helps

 

The z6 oil pickup doesn't sit as low in the pan as the y8. Sounds like your pump is having trouble pulling oil. I hope you let your engine idle for awhile before you drive.