Update 3_build_guide.md

docs/3_build_guide.md

@@ -87,14 +87,16 @@ Ensure you have all the parts from the [`Bill of Materials`](2_BOM.md).
 
    b) m2y pulley: push fit two bearings into the m2y pulley and add washers for now.
 
-      **NOTE**: the tricky part here is making sure the long belt doesnt scrape the motor like step 5e, 
+  **NOTE**: the tricky part here is making sure the long belt doesnt scrape the motor like step 5e, 
 
       so remember to keep the wider part of the m2y close to the x body, 
 
       and place 2 or 3washers between the x body and the m2y pulley.
 
 <img src="images/build_guide/4_x_pulley.jpg" alt="combine" width="400"/>
 
+TODO update m2y image
+
    We have now fully combined x and y bodies!
 
 <img src="images/build_guide/4_combined.jpg" alt="combine" width="400"/>