Help: Identify Rear Bumper Part

[gk3]

Hey,

I was installing my rear diffuser and the white plastic part that the diffuser clips into, one of the tabs along the bottom broke. To keep the diffuser from sitting crooked I had to leave both bottom clips out. Can anyone help me identify the plastic piece part #? I'd like to replace it and install the diffuser correctly.

Edit: Found it, 51-12-8-054-289.