A gas turbine engine includes a case having a wall that provides a cavity. The wall includes an aperture and a bore. A tube assembly with a flange provides a fluid passage aligned with the aperture. A flow diverter is arranged in the cavity and includes a plate with a hole. An insert has a body and a head. The body is received in the hole and press-fit in the bore. The head captures the plate against the wall. A fastener secures the flange to the insert and clamps the flow diverter to the case.