On my Resident return, on the "Adjust this amount" input, what Non-Resident income should be included?

All worldwide income, including all of your New York (NY) nonresident income is taxable to your resident state of Pennsylvania (PA).  PA will give you a credit for the tax you pay to NY on your nonresident return so it's important to complete it first.

State Returns - Assumes both states require income tax returns to be filed: Prepare the nonresident state first.

1. Report the sale in the state where the property resides.
2. Report it on your resident state and receive credit for taxes paid to another state.

Credit for taxes paid to another state is allowed by a resident state when the same income is being taxed to another state.  Your resident state does not want you to pay tax twice on the same income. The credit that is allowed will be the lesser of:

1. the tax liability actually charged by the nonresident state, OR
2. the tax liability that would have been charged by your resident state