Of course, all this stuff carries across to the front-end design of your FM tuner. You can apply the same equations for SFDR etc.
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The spectrum analyzer is an incredibly complex instrument. I have found myself running into rabbit holes when i learn more about it. The attachment 3 and 4 illustrate the complex inter-relationship between mixer limit, dynamic range limit, reference level at the input, mixer and log amp envelope detector from R&S. It is confusing because the 1st mixer is never attached to the log amp envelope detector directly!
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With the older analysers like the HP8566B and 8568B, the log amp only had an effective range of just over 90dB. So, this complicates things when measuring noise near the bottom of the display. In theory, you are supposed to keep the noise at least 10-14dB above the bottom of the log display if you want to measure noise power fairly accurately. This is because the old school logamp can't handle noise properly near the bottom of its log range. This means the operator has to be very careful when measuring phase noise on these old analysers. It's easy to get a false result.
Newer analysers with a digital IF perform much better here. However, the digital IF is going to be prone to clipping problems in the ADC with signals near the top of the display. This is due to the overall PEP of the waveform. Complex waveforms can exceed the ADC input range. Older swept analysers with analogue RBW filters are much more tolerant of this.