Modular Replicator 2 Top Mount Filament Spool Holder

Of all the filament holders out there, I thought the top mounts were the best. During my initial Replicator 2 upgrade phase I used brackett27's design but I soon saw room for improvement.

My main contributions to this type of mount are:
-one part for all 4 sides (instead of left and right, etc)
-modular add in capability (for rods and magnets to hold spools and tools)
-centralizing tube for spools
-improved aesthetics
-less tangling or jamming from too much or too little resistance on spool
-no supports required (follows 45 degree rule)

Note:
I would suggest a few helper disks via makerware
Should be no need for rafts

McMaster-Carr Hardware:
- M6 x 16 mm flange-head socket cap screws to hold the supports in (#92235A238)
- 3x 3/8 x 2' threaded rod - one to hold the spools and two to guide the filament. The threads keep the filament from moving too far to the left and right and wrapping around another spool (#98804A031)
- 3/8 hex nuts (