"TOTAL STATE for the State ID number, and gives the total income and the total tax for BOTH states."

That might be required.

Some States will tax only the locally sourced wage. Some States want you to report all Income and then they credit back the tax paid to another State.

You cannot try to Add the State Wages together and match to Fed, because that is not the reporting requirement. You need to research and understand the specific State's requirements.

Do not proceed with your concept of allocation, until you know what is required. Typically, your purchased software has this built into it, from the W2 entries.