I designed this guide to avoid wear on my Wanhao D12 extruder.
Before i was using this guide it was great but wanted something less imposing :

https://www.thingiverse.com/thing:4695824

|| INSTAL ||
To install this guide you just need an M3 screw, a nut and one or two washers depending on the head of your screw.

Remove the screw at the bottom right of your extruder (photo 1) place the guide and put the screw back.

Place your M3 bolt like the picture 2.