No - I meant what I wrote.

Moving magnet cartridges (I prefer the term 'fixed-coil' cartridge) are relatively immune to the resistive loading: it doesn't matter much if they are loaded with 39K, 47K, or 68K. They are however susceptable to changes in the capacitive loading, and this will depend on actual cartridge and the inductance of the coils. And that is what your 'tuning' kit does; it allows you to change the capacitance by changing the loading plugs.

Most Shure cartridges have a coil inductance of around 500 to 650mH, and like to 'see' a capacitive loading of around 400 to 500pF. The internal arm wiring and tonearm leads will contribute about 100pF. I don't know what the loading capacitance of Glenn's preamp is, but I'm guessing it's around 120pF, so in total you will have about 220pF, suggesting you need to add 180pF with the loading plugs. You will obviously need to experiment and tune by ear, but no harm will be done if you don't get the loading correct.