Changing my radiator because there is always a bunch of rusty looking gunk in the neck. Was afraid some of the tubes might be plugged. Got the old one out. The antifreeze was basically rust colored. Where some of it spilled and dried on the driveway, it left a brown residue behind. Nasty.
Decided I needed to flush the block before putting the new radiator in, so the rest of the daylight hours were spent getting the stuff needed to flush the rest of the so-called coolant out of there. Too lazy to get restarted on it when I got back; I hate working in the dark if I don't have too. Guess I'll finish it all up next weekend.