This fits like it should go between the carb and intake. It has hook ups and a heating coil?
I wondered the same thing a while ago and asked the MM folks.
Here's the thread. Hope it's OK to link to MM forum.
http://www.minimania.com/msgThread/112597/1/1/SU_Carb_parts_info (http://www.minimania.com/msgThread/112597/1/1/SU_Carb_parts_info)
turns out to be a heating coil to prevent carburetor icing. I think some Canadian cars got them routinely. Mine also had a heating band around the piston housing to prevent piston from locking up ( Housing got cold and piston would stick open and wouldn't decelerate)
How dare you! Yes, it's fine, I don't care. Knowledge is power.
Rats I had visions of it being a rare experimental part that slipped out of the factory and is worth big bucks. lol