drybox & spool holder

I purchased following supplies:

1. Steelworks 5/16-in x 1-ft Coarse Thread Zinc-Plated Steel Threaded Rod (Lowe's)
2. Sterilite 20 Qt. Clear Gasket Storage Box, Blue Latches with Clear Lid (Walmart)
3. M3 x 20mm bolt and M3 hex nut (Amazon)
4. M6 Straight through Pneumatic Connector  and  PTFE  Bowden Tubing

and some tools to assemble the drybox:

1. drill and drill bit
2. sharpie 
3. Hex Key Allen Wrench 
4. ruler

customized maximum / minimum  diameter and height of the cone-shaped spool holder.