I just replaced my coolant at 25,000 mi and attempted to bleed it by the run car/top off/run car/top off/etc method. Twice now I've heard the coolant lines either to or from (can't tell just from the noise) my heater core 'gurgle' when I first started the car. I know it's not an immediate danger, but I don't want to be driving with air in my block. Anything I may have missed/looked over to bleed the air out? I ran the car with the radiator cap off, and the reserve tank cap on.

it's more of a "burping" process than bleeding as you are not pushing fluid through the system. Try squeezing the hoses when the car is on. this will help remove air bubbles. if you run the engine for a bit, the bubbles should come out and you can then add fluid. if your temp gauge goes too high, then you know to add more fluid (unless it is allready at the Full-line)

just run your heater on high, watch the temperature gauge, and drive around the block. it should bleed out airbubbles and suck up coolant from your resevoir on your own.