My question is is there any way to modify his body to stay permanently locked? I've considered super glue and possibly drilling a screw through where the head goes, through the bottom of the empty compartment where it meets the grey plastic area housing the mechanism button.

If anyone has suggestions i'd like to hear it since i don't want to risk ruining him by attempting to taking him apart (to attempt to remove the mechanism), he's the only generation 1 style figure of optimus that i own on my relatively small collection.