I got the LED strips soldered and inserted into the cylinder.  I printed retainer strips to keep the LEDs in their slots.  It’s now wired up to the Adafruit Feather Huzzah32 and now running a rainbow trial. 

I taped two sheets of paper to make the diffuser. Not perfect but pretty effective as a diffuser. 

I just need to wire up the buttons (awaiting delivery of the wires and connectors to connect to the two-pin headers include the breadboard to simplify disassembly/reassembly).