David Iím having difficulty posting a pic so I put this link above and hope it works.
The plate has plenty of surface on the sear. Again, it works out of the gun. If the pic works, Iím curious if the tip of the sear or the small Ďsprocketí it sits against when you cock the hammer is possibly not enough surface when itís on the gun. Perhaps itís shifting when the side plate is attached to the gun.