Well, I started flushing out the orange stuff today. I drained the radiator by opening the petcock and also disconnecting the lower radiator hose, then refilled it and ran the engine until it was hot, then repeated that sequence about three more times before what came out finally started looking pretty much clear. It's not supposed to freeze here tonight so I'll drive it a little tomorrow and then drain it one more time to see if it looks clear. If it does I'll refill with water and then drain half the system (need to look up what the total capacity is and then take half of that out) and refill w/ the green stuff.
Too bad I didn't know this sooner. I had been running straight water and just put the orange stuff in yesterday. :(
