Sorry Bogatyr but the flush you talk about is mearly a dillution as the engine block still holds a majority of the coolant.

Now if there was a way to get water into the engine block forcing the coolant there out and drain at the same time until it runs clear... doh I just realized after that you would have trouble getting the 50/50 you need...

There is no way around a good coolant change. You MUST remove the damn and most dispissed engine "plugs". If you don't have a lift get yourself a head-light so you can see the darn bolts.