Here is what are called shrimp lights. They are green but looking at the picture you can see how it is made. use a PVC tube on the inside and wrap the LED's around use PVC caps with a clear lens. I would much rather use a diffuesed lens if you can to scatter the light and not make it so bright if you look at it. LED strips can be found on Amazon. If time is not an object Chinese sites like
www.Bangood.com or
www.GearBest.com have them cheap.
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ooh I really like that. Put a hangar hook on one end cap, put 10-20' of leader wire inside the pipe. In use you hang it where you wan the light and run the cord to a 12v source. Anderson power pole connectors, or clamps, all kind of connection solutions. The storage arrangement ikk posted is idea IMAO. The battery weight centered in the middle, pockets for the light tubes (or the other pre-made ligth sources I mentioned earlier) on the flanks of the case.
Add a plug at the hangar end and you could daisy chain them to each other for a long spaced run, with the power source at the end of the chain.
A few months ago I tried out some of those cheap chinese LED strings, they were a neat solution for what they are. I used them to trim out the hatch on my Suburban with red LEDs, chiefly for field use in my astronomy hobby.
One could even make the light tubes with white LEDs but fabricate clear red plexiglass sleeves to shift to red light is desired. Or interleave strings of white and red LEDs and mount a three position switch to change from red to white light. All sorts of possibilities here.