Integration Manager Sales Order Processing Error

[TallOne]

Hello,

I'm integrating Items and Customers w/o error. I'm working on Sales Order
Processing now and get this error:
Doc 1 Error: The default site is not assigned to item xxxx
I do assign it in the Inventory Integration specifically in:
Inventory Item>Qtys/Sites
Field=Default Site ID
Rule=Use Constant
Source=WAREHOUSE

I've also assigned it in the Sales Transaction Integration here:
SalesTransaction>Items>Item Detail
Field=SiteID
Rule=UseConstant
Source=WAREHOUSE
But this doesn't seem to make a difference. Anybody got any suggestions?
Thanks
TallOne