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Click on PayPal under Methods and it will go to this screen.
Click the Integration Method (drop down field) and select Website Payments Pro (Express Checkout and Direct Payments).
Click on the Advanced tab in the upper right corner for more options:
The page will then expand where you can locate "Setup First-Party Credentials" (highlighted in red box below)..
Here's where you use the information you obtained from PayPal.
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