There are varying opinions on the effects of a hopstand or whirlpool at different temperatures. The 175-180 range is suppose to give you the best utilizaion of the hops for increasing aroma. That's where I've been doing my 20 minute whirlpool for IPAs. Google hopstand and you'll find many articles regarding this.
That being said you're on the right track. After flame out chill your beer to the desired temp and then add your hops, cover and let it stand for desired time.