No worries, it fell out long before I got this far and I heard it bounce around inside. Set it aside once I got the lid off and it rolled out.

It fits in this small stand-up slot that doesn't seem to hold the square nut in .. so a dab of white glue to keep it there while the work is going on did the trick.

No they cannot , I see zero listings for echo motherboards. If the part was produced here would be listings. Amazon produced just enough and shut production down. Manufacturer of ewaste is best I can classify amazon as given the electronic device just does after 5-7 Years of at most using electricity.

Without a source for replacement motherboards this guide is useless.