Download the files from http://www.thingiverse.com/thing:1094616
Scale up the parts from above 150% except for P2_Sun_P3_Sun which is 149%
Print my parts at 100%.
Some parts require supports.

Stuff required:
4 mm shaft - 2 pieces about 185 mm and one piece about 220 mm
18 gauge brads - 5/8" long
self-tapping screws - #4 1/2" and 3/4"
set screws and nuts - #6 about 1/4"
extension springs - 13/64" and 13/16" - Harbor Freight Item # 67562
small eye screws
Gear Motor - https://www.amazon.com/gp/product/B01KTZXZDE/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1
Motor Speed Control Switch Controller - https://www.amazon.com/gp/product/B019H4DDIA/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
12V 2.5A AC-DC Adapter - Radio Shack Item # 273-318 or similar or 12V battery.
PWM Controller Housing - http://www.thingiverse.com/thing:1958914 - needs to be stretched.

Assembly Instructions:
Clean up the parts after printing them.
Assemble the transmission as shown at http://www.thingiverse.com/thing:1958914 but do the following:
Put C2 Clutch Fork in Case before putting C2 Clutch Slider in Case.
Put C1 Clutch Fork in Case before putting C1 Clutch Slider in Case.
Put long bushing between rear of case and clutch button.
Put short bushings between clutch buttons.
Drill holes in case for springs.
Looking at the front of the transmission, the large gear should rotate clockwise.