I've had a forearm-less energon Optimus ever since my WFC Ironhide custom.
Realised last week I could use the forearms from a KO Classics seeker and the pipes from a KO transforming truck to make some new forearms. They're screwed on.
I used a spare CW Vortex head - to me it goes with the toy and MTMTE model.











Imgur was playing games with me: hopefully the images work