This months issue of Super Chevy magazine (september 2002) has some great cooling tips. Here's a picture of how to drill 1/8th inch holes in your 180* thermostat to purge air from the engine when filling the system and as it warms up.

Here's the Cooling Article on page 86.

And here's the magazine cover.

Thanx for posting this , I'll have to go pick up the mag !