Cloudlifter or FetHead for an SM7B: what do the 2 dB change?
Yes. With the FetHead already in line, the Scarlett Solo (Gen 3) only has to supply about 32 dB of the 56 it publishes. Those are the published figures.
The hard gain is already done. The Triton Audio FetHead sits in front of the Focusrite Scarlett Solo (Gen 3), so the interface preamp is no longer the thing that has to rescue a quiet microphone.
Shure rates the SM7B at -59.0 dBV/Pa, the voltage from a loud 94 dB tone at the grille. A speaking voice is closer to 85 dB, so the preamp still has to find about 32 dB to land near −9 dBV. That −9 dBV figure is just a tracking level: high enough to use, with space before the converter clips.
Feed the interface from the booster's output and do not stack a second microphone preamp on top. Most inline boosters spend the 48 V themselves. That is fine for a dynamic. If this microphone is a condenser, read the booster's manual before you leave it in the chain: if it does not pass phantom, the capsule goes silent.