Z Axis Lead Screw Modification

This is a modification of the Z Axis for the Cory D-Bot. Links two lead screws together with 970mm belt and pulley system all contained on single rail.

Idler modified from: http://www.thingiverse.com/thing:2179222


Parts used:
NOTE: The 976mm belt is for a 300mm wide bed !

976mm Belt (1): https://www.amazon.com/gp/product/B018HOII3Q/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
Stepper Pulley, 16 Tooth, 5mm (1): https://www.amazon.com/BIQU-Aluminum-16Teeth-Timing-Printer/dp/B01HXNR8W4/ref=sr_1_9?s=industrial&ie=UTF8&qid=1492482110&sr=1-9&keywords=16T+GT2+pulley
Lead Screw Pulley 60 Tooth, 8mm, (2): https://www.amazon.com/gp/product/B01FVV9184/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
Toothless Idler Pulley (2), 5mm: https://www.amazon.com/gp/product/B01H3F8LUU/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1
Lead Screw Bearings 8mm, 608zz (2): https://www.amazon.com/gp/product/B01EVX83BO/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1
Lead Screw 8mm, 4 Start, 500mm (2): htt