Anybody
> out there have any problem with the metal screw.  I could see it if you
> torqued it to tight, but if it's just snug I don't see a problem.

I have the metal scew in my '85, removed it the other day to check 
for air with all this coolant talk!  Metal is fine, don't overtorque, 
use a little good Loctite gasket maker/sealer (NOT threadlocker) on 
the threads and be happy.