Input to the RSP is 0dBm continuous and 10dB for short periods.
Dynamic range will for the most part be decided by selection of IF frequency.
Generally, the ADC will start to overload when the input signal reaches around 10-15dB higher than the reference level set on the analyser. 0dB input is OK but will leave you little room for error. It might be worth having a few in-line attenuators that can be used between the dummy load tap and the RSP if required. This would allow you to use a lower reference level setting, with the advantage of a lower noise floor.