Ok, I've done lenticular graphics before (although I did it digitally rather than screen), so let's see if I understand what's going on here:
1: Your finished image is made up of vertical lines, each 1px wide.
2: Because of printing inaccuracies, it's nearly impossible to get the lens to line up perfectly with the lines, so you want a slight "gap" between each pixel.
If that's the case, then try this:
1: Work out how much smaller the gap should be compared to the lines (let's say, 10%)
2: Enlarge your image 10 times (1000%) using "Nearest Neighbour" resampling method.
3: Create a new Photoshop document, 10px x 1px, transparent background
4: Draw one white pixel at the right edge (or whatever colour you want the gap to be).
5: Select All, Edit > Define Pattern... and give it a name.
6: Go back to your original image, and go to Edit > Fill...
7: Choose "Pattern" and find the pattern you just made.
You may need to adjust the resolution (with Resampling turned off) to match your finished printed size. These graphics are very tricky to get right, but the results can be amazing once you get your settings right.