All Grain Cherry Wheat- how much cherries to use an how to prepare them

Started my first cherry wheat yesterday and need a little help with type of cherries and how much to use. Here is my recipe below:

14 gallons boil
35 min boil with 2 oz cascade hopps (7.5%AA)
20 lbs of grain (both malt and wheat)
2lbs rice halls
Two primary fermenters with 6 gallons of wort
Safale American ale yeast US-05

This being my first cherry wheat I am not quite sure on how many lbs of cherries to use and whether or not I should buy in puree form or start with fresh cherries….being from Michigan I was hoping to use some cherries from Traverse City. At the homebrew store I was warned that you have to be careful with using fresh cherries since there can contaminants of the cherries themselves. Would boiling the cherries in a muslin bag be a good idea when adding to the secondary fermenter? How many lbs of cherries should I use in each fermenter? I’m looking to make this cherry wheat a little les milder in cherry flavor than sam adams cherry wheat. Any suggestions/input would be greatly appreciated. Thank you in advanced.

-Rob

For fresh fruit, I usually use about 10# of fruit that is macerated, for a 5 gallon batch. I have boiled cherries in the last 15 minutes or washed them and added to primary (for a lambic). You could boil the cherries in a bag. For puree, I have used 1 can of Oregon juice for a 5 gallon batch and achieved nice results. Should be a good batch.

ya i was looking at using 8-10 lbs of cherries in each fermenter...clean them, mash them and then fill a bowl with water and add some pectic enzyme drops and campden tablet and let sit in the bowl over night in the fridge and then add to the secondary..any thouhts about this idea?