He can allways have a custom seat made would change his knee postion . I rode my buddies Stud Hoss years ago he was a big boy 6'7 and 370 lbs , he had that configured to his liking but ended up selling it after a few years and went to a full wing but had the seat built up .
Highway pegs and I have seen a guy built a set of plat forms that went from the pegs up to the crash bars , they were like nerf bars on a jeep but had a deck up front .