I did this design years ago for a freelance client. Can't remember who the client was, can't even remember exactly when. I think it might have actually been around 2001, but I put a 2004 copyright note on the artwork. I think the clients' company might have been called SGD. Heck, I can't even remember if I got paid for the work... but I think I did.
This is the back view for the medium federation mech along with half of the supplemental detail drawings. The front view has the other half.
There were 4 mechs in this series. I'll eventually post all of them.