> 
>  I'd like to change the coolant in my 86 Synchro this weekend.
> 

I changed mine a few weeks back.  I didn't add the tee, but I removed
the gravel guard under the passenger-side head, and used the handy
drain bolt there to drain out the old stuff.

Then I flushed with some Prestone radiator flush.

Then I flushed out the system by filling with water, following the
bentley's tips of raising the rpm, opening the radiator bleed screw,
opening the bleed screw in the engine compartment, etc.

I flushed the system 4 times with water, to make sure all the radiator
flush stuff was out.  Then I added 2.5 gal of VW antifreeze, and
I added a little bit of water (some water can't be drained using
just the drain plugs in the heads).

It's not real complicated, just time consuming.  If you're doing this
by yourself, I found that folding up some paper, and placing it between
the idle set screw and its stop will provide a nice 2000-2500 rpm, so 
you can walk around to the front, and open the bleeder screw at the 
radiator, and let all those nasty bubbles bubble out.

I collect all my waste fluids (oil, antifreeze) and put them in plastic
milk jugs, to be taken to the local hazardous waste dump site.  I usually
take my oil to a nearby service station or lube parlor, and just dump it
in their tank.

-Jim