I have an od 833 and I don't like it. So I'd switch to a 1 to 1 4 speed before going auto. People think an od is going to save fuel and be the magical solution ....... yea if you drive like miss daisy to piggly wiggly.
I'm usually kicking down to 3rd which is 1 to 1 just keep it responsive and full of pep. When you up to OD, the engine sort of bluh on its face and you're not going to maintain 75+ in OD. also have 2.94 gears out back so if someone is going to have an OD, then 3.23 gears or Lower is probably going to work better, otherwise you're going to be constantly kicking down and keeping the RPMs up in order to get power and maintain speed and the mpg is going to go straight down the crapper.