From what I remember, all, HEI factory installs use 10 gauge wire. I would think there might be a reason for that.
Also, most manufactures will use what ever is cheapest & can get by with. 10 gauge wire cost more than 12 gauge wire. I do not think they would just throw in something that cost more for no apparent reason. Just a thought.
No tension with my comments, just typing what I am thinking about.
