Back to the subject , to solo over a progression you first need to know your soloing scale ... You can guess it (you'll need some experience for this) or do your homework and analyze the chords .
About which notes fits better to which chords and from which octave, that's just a matter of tastes , you should practice jamming along with rhythm tracks a lot , you'll develope your own taste of improvising by time.
One trick Marty Friedman uses , is to arpegiate the notes of the chord that's being played (you can never go wrong by doing this) ... Actualy this is quite helpfull to move to a different octave , but you'll need to develope your sweep picking technique to a decent level to be able to arpegiate faster.