Just pulled my /6......Now I need some answers

yeah, I agree with the 727 in your case. In a light car like a dart, the milage difference will be negligable. With the 360 and the 904 combo, youd better have an extra trans as a spare.
(you probably wont be able to keep your "foot" out of it: its gonna be fun!) thats why the 727 will be a better choice; more peace of mind.