Bleeding the GTV6 cooling system

[Vangelis Kokkevis <vangelis@aw.sgi.com>]

I had the "pleasure" to spend the last two evenings removing and
reinstalling the radiator on my GTV6.  Before I started the operation I
checked my CarDisk for any relevant information on how to go about it
and I found one small paragraph in some shop manual regarding the
removal of the radiator and a page or so in the owner's manual on how to
drain and replenish the cooling system. 

Tip #1:  The shop manual suggests removing the radiator from the car
without removing the fans that are attached to it.... Unless if you are
willing to do some serious detective work to disconnect the fans from
their power supply, remove the fans first!

Question #1:  The owner's manual says that one should start adding
coolant with the bleeding screw open until coolant flows out of the
bleeding screw.  Then the engine should be started and left running
until all the air bleeds... Well, in my case, nothing came out of the
bleeding screw.  In fact, I took it out completely and it seems like it
goes into a blocked threaded hole.  There was no sign of coolant there! 
I left the engine running until I wasn't getting any more air bubbles in
the cooland reservoir... That's the only way I could see bleeding the
system...  Any comments?  What did I get wrong?  

Thanks,

Vangelis
Santa Barbara, CA
85 GTV6
83 Spider