Hi Phil when you go to reply at the bottom of the reply section if you click on " Use Full Editor" then you will see attachment manager and that will allow you to add pics, if you use Post Reply you can't add pics.
Anyway I see you motor does have an alloy head so that can be removed and rotated so the plug is at the top. Post up the bolt centers and we can check if a Victa 125 head gasket is the same