I hate to be the Jeff Berlin in the room, but why worry about this?
Instead of spending effort and time working on playing without looking - spend that time practicing something musically useful. The playing without looking thing is a hang-up people worry too much about. If you spend the evening staring at the bass instead of interacting with the band and the audience it is a problem, otherwise it's a part of playing.
Would you attempt to do carpentry without looking?
Do you Drive without ever checking the gauges?
Do you make love exclusively in the dark so that you are focusing only on the physical feelings?
Why would you deny yourself the ability to check your position if it makes you more confident in your position and thus able to play with less stress and thus play BETTER?
I look occasionally, but when I'm reading charts (or unusual chord changes), although very musical, I have to watch the sheet.
Practicing reading is something very musically useful--- gets me gigs.