Retrofit FLSUN i3 Large printer with Microswiss direct drive extruder

Had a FLSUN i3 large printer that was not working well. Replaced all the aluminum extrusions with 2020 and 2040 v-groove extrusions to stiffen up the frame. Replaced all the fasteners with t-slot nuts and screws, so much better. While at it, replace the extrusion with a micro-swiss direct drive unit kit designed for the Ender 3. I did a remix of Satsana fan duct https://www.thingiverse.com/thing:4369859 to add the X axis limit switch and for the proximity sensor. Now I have a large format printer with direct drive. Printing with TPU is so much easier.

The Z axis brackets were also changed to clear the v-slots for the belt.

When printing the fan duct, make sure there is no support in the air path for the filament coolers,

When assembling the X axis, on the pulley side, only use one of the pulleys and rout the belt into the V-slots, makes the belt shorter.

link to parts:
https://store.micro-swiss.com/products/micro-swiss-direct-drive-extruder-for-creality-ender-5