Wear gloves! Fingerprints and cat hair will show up on side-glow acrylic like beacons, so keep it as clean as you can. Mirror Glaze plastic cleaner can help buff out any fine scratches.
I think it looks best to stack the runes with the most detailed on the bottom and the simplest on the top.
Cut some gaffer's tape to the width of your stack and tape the runes together securely, pressing the tape down hard with a flat metal tool like the back of your scissors.
Carefully slice away a thin strip of tape in the places you want the light to shine through. The pixels will wrap in a slight spiral around the stack, so I removed one strip of tape on each side along that spiral.
Solder up your neopixels with 3 wires. I found it easiest to solder the data wire (in the middle) on the back of the strip, and the power and ground wires (on the edges) to the front.
I keep a gemma loaded with neopixel strandtest code handy for testing. Be sure your pixels work before moving on; it's much easier to fix it now.
Cut another piece of Gaffer's tape to slightly wider than the height of your acrylic. Lay the neopixel strand along it diagonally.
Wrap the tape around the rune stack, lining up all the pixels with the un-covered edges of acrylic.
Hook it back up to your tester and look at the pretty lights! Peek in along the edges to be sure each layer has the neopixels aligned as well as possible.