I suggest you checkout the backwoods forum on their website. plenty of good info over there.
I believe there is a mod to boost the ash pan using angle iron so you dont have to deal with the lip.
5hrs seems a little on the low end IMO for run time but my chubby is 6" longer (lol) and running dry I did a 10hr cook with plenty extra at 250-260.
My guru tends to overshoot 10 degrees if I dont have to very closed up