You'll need to print a total of 12 of the LED guides in transparent plastic. I chose PETG, but because as LEDs do not give off much heat, PLA or other types of plastic should be fine. It's important that the LED guides be printed in a transparent or translucent plastic.

I used my slicer's "fuzzy skin" setting to increase the diffusion effect. The LED guides do not need support.

The remaining 3 parts need one copy each: There's a top, a bottom, and a middle part. The top and middle parts do need support on build plate only. Flip the side with the hexagonal 'holes' down on the build plate. Make sure to turn off the "fuzzy skin" mode if you used it earlier. I printed these in white, but you could use other colors or even make these out of transparent filament too.

First, remove the silicone tube from around the LED strip. Insert diagonal cutters in the end and cut away the end cap and at least an inch of tubing. Then, carefully remove the whole end cap and separate the LED strip from the tubing. Repeat at the other end. With the 1 meter length, it is now possible to carefully pull the strip out of the tubing. With the 5 meter length, it is probably necessary to slit the whole length of the tubing.

Separate the strip into 250mm sections by counting off 10 of the divisions. Make a clean cut exactly along the dividing lines using diagonal cutters.

Next, for each section, cut a generous length of red and black wire (4 inches is good, but I probably did about 6 inches. This leads to some waste but it's preferable to ending up without enough wire). Slightly strip one end of each wire (even though I keep my fingernails short, they were a good tool for this task; the traditional wire strippers I own were not "up to" dealing with this small and thin wire).

Now it's time for the part that needs a lot of care: inserting the LED strip into the 3D-printed LED guides. Identify which side to insert the strip from, and which direction the LED strip needs to face. You'll need 6 strips inserted from each direction; the strips should all face "out".

Count out 24 hex nuts from the box of fasteners. The top and middle pieces each have 6 spots for horizontal nuts and 6 spots for vertical nuts.

If the "horizontal" nuts are a bit loose, you can put a small piece of masking tape over them so they don't fall out for now. Remove the tape when assembly is complete.

For the "vertical" nuts, it's important that they be well-centered with respect to the holes in the 3D prints. You can press them in by taking advantage of a hard surface like a table, and then use one an M2.5 screws to make sure that they are centered before continuing to the next step.

Next, solder the barrel jack onto the perma-proto board. You must place it exactly in the position shown, with the front pin in the top row, the rear pin in the 4th row, and the middle/side pin in the third row.

Bend the top pin down, the bottom pin up and the side pin right.

Using a small piece of wire, create a connection from the top pin to the topmost pad with the blue line to its right.

This will connect the power supply's positive side to the red (positive) rail and the negative side to the blue (GND) rail.

The Perma Proto is shown here on top of the bottom 3d printed piece, but at this point you should not screw them together. It's good to check the base part for correct fit, though, it could save you a tricky unsoldering operation later.

Instead, set the bottom piece aside and bolt the middle piece to the perma-proto in the orientation shown. You won't have enough screws to fill all 8 positions, but 2 or 3 provide an adequate mechanical connection.

Grab some of the middle length (M2.5x6mm) screws from the fastener pack.

Pick two LED strips of the correct orientation to go in the north and south positions and screw them in to the base piece and then into the top piece.

Take the red wire of the south piece and "thread" it through the bottom hole just to the right of the red line. Take the black wire and thread it through the bottom hole just to the left of the blue line.

Then, grip the bottom part of the black wire with pliers and use your fingernails to strip the insulation at least 1/4" from the end. Push the remaining insulation back through the hole, and solder the exposed wire to the pad. Repeat with the other (red) wire. Trim any excess wire with side cutters. At this point, it's good to test the LEDs by plugging in the power supply and turning it to 10V or more; the LED strip should light clearly along its entire length. Always unplug the power supply before soldering the next strip.