I've been getting this a lot the method I've been taking is to delete the face I'm dividing then draw the dividing lines in, then selecting each subface to remove any extra faces using the delete tool. at times I've had 4-5 stacked faces that I've had to remove before I started doing the above. oh and an easy way to find stacked faces other than the Xray face mode (stacked faces show up darker) is with the paint tool.. if a face won't paint, it's stacked...

Try component_instance.transformation.to_a - it returns a 16 item array that has all of the stuff you need like scaling rotation and location. You really need to use all of these to compare distances between components etc as they might be rotated, scaled etc as well as moved in XYZ... The 16 item array has items 12,13,14 == x,y,z .