SmartrapCore 1.2x new slideX with back-sided fanduct

This version is osbsolete. You might be more interested in the new one : http://www.thingiverse.com/thing:1190481

The original SmartrapCore 1.2x (I currently use V. 1.24) slideX part is very well designed and effective, but in the process of designing a project for a twin-headed version of it (http://www.thingiverse.com/thing:995640) I got some ideas that seemed to be usefully adaptable to the single-headed regular parts, at least with one goal in mind : putting the printing zone cooling fan