RE: Intermediate frequency, Question?
The first IF is 10.7 mHz which is obtained by mixing either 61.530 mHz or 82.930 mHz ( I don't know which) with the incoming channel 22 frequency 72.230 mHz.
The second IF is 455 kHz which is obtained by mixing either 10.245 mHz or 11.155 mHz (again I don't know which) with the 10.700 mHz first IF.
I don't think either of these mixes determines positive or negative shift. I believe the positive/negative shift is part of how the signal is modulated.
Guess its time to disect a receiver and see what really is going on in there.