"the FPV indicator will start to move towards the 'Airplane symbol' on the PFD."
I don't think this is possible. The FPV displays in pitch the angle of the Flight Path relative to the horizon. The a/c symbol displays a/c attitude. The FPV will be displaced sideways from the centre position on due to drift and this reflects the Track Line. We all know that B737 flies level between 6 degrees & 2 degrees nose up depending on speed. The FPV will be at ZERO degree on the PFD. The a/c will climb at low/medium levels about 7-10 degrees and the FPV will be significantly below that. It'll descend from high level 290kts with about 0 degrees; the FPV will be below that. On approach the attitude is 1-2.5 degrees and FPV is -3 degrees. In my experience it is impossible to stabilise the FPV on top of the a/c symbol.
I once saw a PPL'er in a fun sim session. He'd done the apptitude tests where you move a small square to follow a moving dot on a screen using a joy-stick. He tried to do the same with the FPV and a/c symbol similar to a Flight Director. It is impossible and he was very confused, plus we ended up in some very interesting positions.