360 LA oil pickup

The stock pickup is meant to touch the bottom of the pan as the screen is recessed within the pickup to allow the clearance needed. Aftermarket pickups may not work that way unless it has a similar clearance creating bar or recess. If the aftermarket pickup is simply a flat screen you will need to leave clearance from the bottom of the pan to the pickups screen to allow oil flow.

There are other threads on this site that cover the required clearance for these types of flat pickups.