[fp1529]

I am in the middle of replacing the fuel pump in my 99 1500 suburban (old body style) 350. I have the tank off the vehicle but can't get the new AC Delco fuel pump to seat. It seems simple it's only the fuel pump, o-ring gasket and an almost full circle locking ring that slides under tabs along the circle. I really want to get this done. Is there a secret? Please help!