Warmed up, no strange sounds in motor bay, almost silent, but when standing behind some very weird high pitch metallic clanking.

Feels like exhaust pipe issue, maybe rubber mounts hardened because of cold or old age.

Vid here:
https://youtu.be/zNSq4JbPxVw

 

depending on how your exhaust is set up, thats sounds perfectly normal. but, I would have to say you have a vacuum leak as you have a bit of a lumpy idle

 

thanks, will check it too

 

sounds like a cheap muffler with no sound absorption qualities to me, yep.