I agree - no line filter is needed. I'd say also that no extra trim plate is needed either unless the metalwork has been messed up. I changed my 130s to IEC recently by filing out the hole periphery with a 3/8" D or so round file just enough clear the chamfer and rounded corner features of the IEC connector. The original hole shows a bit, but I don't mind since it's on the back. Here's what it looks like: