Weller base slide lock plate

Ever notice that a Weller solder station has slots on the bottom for mounting? Well I needed to be able to lock the base unit onto a portable rig and I noticed it was there...
Did some searching, checked their site, couldn't find anything that would fit the slide lock joints that were right there on the bottom.
So here is my attempt to make something that does! Hopefully the next person in need will find this and it will work for them too :-)

This is a rectangular baseplate for WES51 (should fit the 51D??). Mates and slides easily, the friction of the rubber feet holding it tightly in place.
Mounting holes are for M4 screws (in the photo you can see them threaded into inserts which I used to provide a hard attachment point in plywood).