The 580B is similar to my 480C using the ether assist mechanism on the 188diesel. It is located at the left rear corner of the block. I've attached a picture, so you know what it looks like.
If you are fortunate enough to have it near an electrical outlet, they also made block heaters for them. Item #40 at the bottom right of the second attachment.
I had a 530 diesel w/188 several years back. It did have a manifold heater. I may check, and see if the manifold number is the same as on my 480C here one of these days. I would much rather have that, than ether assist, which I don't use. If I need it real bad this winter, I may give it a sniff out of a can.