CR hotend, modified

I must say again that the fundamental design by holyfarrier is brilliant. I started working with this design about 3 months ago and fell in love with it after finding that it achieves the following key features for me:
1. Quick access to nozzle by rapid removal of fan duct.
2. Highly effective part cooling even down at low PWM levels (I'm talking 10% fan levels). Very efficient. The same old fan levels are now overkill with this setup which is truly advantageous when you are trying to optimize part cooling.
3. Nozzle proximity to X gantry 2020 extrusion. Other designs leave the nozzle further from the x gantry than is desirable. This causes all kinds of issues. The least of these issues is y axis calibration. With the stock Cr mod, you lose about 7 mm of a total of 230mm on the ender 3 where others will take up about 15 mm or more.

The summary of my modifications:
1. Redesigned the interface between the fan duct and the drive mount. In my make of this design, I added