Maybe I'm a little " stupid " and don't understand your way of thinking or what you are looking at and I said that because you are thinking to in the time add a SUT to the CH and what do you need to add that SUT?:
well obviuosly the SUT and an IC cable and what does that means?
that the valuable and way sensitive cartridge audio signal not muts pass through a pair of additional SUT input connectors that degrades that signal as does too the solder joints and from there the audio signal will continue hislong tortuose path through the " hundreds " meters of transformers wires that react to the cartridge signal and that follows the degradatio but this is not the end because the signal now must pass for other pairs of SUT output connectors and solder joints along the IC cables. Why all those long totuose path against your today DIRECT cartridge audio signal path? Makes sense to you? if yes, then go a head. No problem with me.