I know he has bought a LPF for his application, but this is for kicks.
He had done a 4 resonator BPF design. It had a high spread of inductor valu es. It was canonical and had over 80 dB of suppression at the 2nd harmonic (ignoring loss).
What I have here is a 4 resonator tubular design where all inductors are 10 uH. (Keeping them equal, it is possible for the 50 ohm filter "class" I ma de to have the inductors anywhere between 6.8 and 27 uH, using the Norton t ransformer and R-scaling.) Tubular filters are not canonical. The design th eoretically has over 90 dB of attenuation at the 2nd harmonic for the Q val ues given in the ASC file. It is physically symmetrical. The heavy bias of poles at infinity was intentional because the main purpose is harmonic filt ering.