Printrbot Extruder Remix

I used TinkerCAD to mash up thing:281015 and thing:446480. I've also ran these through the netfabb cloud client to repair any mesh discrepancies. I've also added the pin from thing 281015 for completeness.

Standard Arm Version:
https://tinkercad.com/things/1zOgEpKKkNh

Left Arm Version:
https://tinkercad.com/things/cjlAE4hfMGQ

Extruder Base:
https://tinkercad.com/things/0KpDCJTWMsa

Extruder Base Left:
https://tinkercad.com/things/332oORRDXI1