There are two threads from 53guy that were highly popular fender trimming write ups back in the day. His hosted images have since been lost, but the threads have been archived online thanks to kastien.
So I have 2 versions of the the hooker's (if you aren't a flying type, this isn't an insult to people who don't have real tail rotors) write-ups with pictures saved.
One is the one the version originally save by Jon and then Kastein that is linked above which still has pictures, but is a little messy.
The other was saved by Yuccaman (and then by me) that you can find, with pictures, on his website.
There is also the Stump method which takes a little bit more fabrication, but if you don't want to run flares and you get it right, like he did, then it looks nice.