I've never wrestled, but it seems to me that unless he was kind of a pudgy 165, moving up to 174 would be easier. Most 17-18 year old guys are still growing and developing physically, so moving up a weight would be easier. I'm assuming that the strength and conditioning coaching and facilities at a Division 1 university are far superior to those at a typical high school, so the few extra pounds are likely to be 'good' weight and shouldn't adversely affect his stamina or flexibility. Of course I'll gladly defer to anyone with actual experience in this field.