i halve a 1952 chevy pickup 1/2 ton i just bought it has been changet over to 12 volt but the altenator has a box attached on the out side of it one wire from altinator goes in to it one wore comes out and goes to wiring hornace one wire conect to post on altanator and goes to wiring hornace what is the small box for ? i halve a picture of it not smart enought to post it


floye mungle