Last Wort Hopping

I developed my own wheat recipe and will be brewing it later today. I am going to try some last wort hopping with it. I plan on adding 2oz of Fuggles right after the boil. My question is, how long should I let them sit in my brew kettle before I start to cool the wort? I have always immediately cooled the wort after the boil to minimize any contamination. Any advise or techniques that I should be aware of when doing this? Thanks......

I usually do my hop stands for about 15-20 minutes before chilling.

There's a couple ways. It sounds like you're doing knockout hops. I do this all the time. I've steeped them up to an hour for a black ipa. For a wheat, I'd go no longer than 15 min.

The other option is whirlpool hops - wait until your wort temp is less than 180, then add them while you continue to cool.