It is always possible and in fact the circuit already contained an inductor which was 30% of the overall inductance value that I quoted to you. I did not wish to complicate the question by including this detail. What is does do is reduce the overall sensitivity to inductance of the LDC1000. Although at low frequencies ~5kHz the inductance measurement can have a resolution of up to 24 bits (as stated in the datasheet as a headline value), when the operating frequency is 5MHz, the resolution is significantly reduced and for an inductance change of 30%, I have recorded a change of only 290 bits on the EVM system, where the clock I guess is 8MHz (I cannot find this recorded on the datasheet). With the EVM GUI setting of 4096 samples this increases the resolution from approx 8 bits to 8+(sq root of 12 bits) - due to sampling and so gives a total of approx 12 bits and a resolution of 0.001uH Inductance change.
That said - do you have an answer to my question about ways to confirm Rp without an impedance analyser that would help other users and implementer's?