Select all outer edges of an object all at the same height (plane)

[ken_newmanA5SM]

I have a complex extruded object (See attached), and I want to fillet only the outside edge of the object. For this object, all the outside edges are the same height (on the same plane). Is there an easy way to select all of them by holding <CTRL> and manually selecting all of them individually?

[jeff_strater]

Hmmm...  There is no way that I know of to do that.  I would probably create a selection set, and incrementally add the outer edges to it, so that you don't accidentally slip and unexpectedly unselect all the edges you have selected so far.

[jhackney1972]

I made a quick model, I wish I had yours, to show you my method.  The video will explain.  If you miss some, because of the side you are looking at, simply turn it around and do the process again.  Overlapping selections will not hurt.  If you would attach your model I will try the process on your model.  As I show in the video, make sure "Select Through" under the selection filters is off and when selecting the second ground of Faces/Features be sure to use a Crossing.

[HughesTooling]

How about creating the part solid without the hole through first? Then add the fillet by selecting the top face then extrude cut the cavity through?

Mark

[TheCADWhisperer]

@ken_newmanA5SM 

Through a combination of @HughesTooling suggestion and @jhackney1972  demonstration - this is easy to window select all outer top edges for fillet (the question becomes - can a valid Fillet feature be created). 
Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply if you can’t figure it out?

Edit: Yikes! Just select the face as suggested by @HughesTooling I did not read clearly the first time through. Then Thin Feature Extrude through all - Intersection.