Actually, once you know ONE position, you can work out the rest from that point onwards fairly easily.
In fact, it might be better for you to try and work out the notes by ear, rather than by trying to memorise scale patterns on the neck - it will make you a better guitarist.
I always say the BEST thing I ever learned in my guitar playing was 30+ years ago when a session musician showed me the minor pentatonic scale. The WORST thing I ever learned in my guitar playing was 30+ years ago when a session musician showed me the minor pentatonic scale! 
It is all to easy to get locked into the 'patterns' and that will make your solos sound just like everyone else.
What I am working on at the moment with my teacher is, for example knowing the position all over the fretboard of every 'A' note. From that, we can build the scales around them. It is amazing how 'freeing' that is, when you become more and more familiar with the neck, and can move easily from position to position with confidence and still hit the right notes.
I am still a long way off personally, but it has given me a whole new perspective on the fretboard, and indeed, made me think about solos in a more musical fashion, rather than just fixed licks in fixed positions...
Good luck with your learning!
JBLP Gold Top #129 - redubbed "#1 in Oz"