The Puree should be more efficient than real fruit, So I'm guessing that maybe 6#? would be pretty strong....nice though.
I would not go any less than a week on the fruit, but taste will tell. Try and ignore the rest of the funky flavors that you'll taste and try to make your palate look for the fruit flavor only. When it suites you, you're good.
Also, be very careful racking off of the fruit. That Puree is super easy to disturb, and doesn't compact much. Expect to rack at least 2 more times before you are clear enough to bottle.
Sounds pretty good! Good Luck!