Chelan Butte seems to have the best genetics...out of those 3 options. Personally I like the Manson Unit but unless your buddy is one of the 3 people who have already contacted me, that would be hunter #4 in this unit and that's a lot of rams to go after in the Manson unit where you spot the sheep from the lake and then hike up to them!
I don't know anything about Mt. Hull, other than its near Oroville...my advice is to drive to the top of the Butte and break out the spotting scope, then tell your buddy you will pick him up at the bottom of the canyon he wants to hike down, then repeat each of the canyons, looking for the rams...Oh, and the band of sheep like to move towards Howard Flats and Union Valley as well, not sure the entire boundaries for his hunt, but there are a few nice canyons on the backside of the butte that are worth exploring...and a "giant" ram is in the eye of the beholder...for me, any ram 3/4 or better that is broomed would be "giant"...or a full with lamb tips...in other words, any older, mature ram!
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