The Alabama Department of Revenue discourages individuals from making installment plans. If you do not pay the full amount due by whatever means possible, they will issue a final determination which is not appealable. This is in fact, the level of a judgement, and tax liens will be filed.
You need to find a way to pay them at least a partial payment.
I went to the Alabama Department of Revenue specifically to ask about this question. The response, copied below says that you can make a partial payment.
"We have received your request for partial payments of your individual income tax liability. We will credit any voluntary payments made, however, we are not authorized to set up payment plans. Also, voluntary payments will not delay further processing of your file. Further processing may include entry of an assessment, filing of a tax lien and transfer of your file to the Collection Services Division.
Voluntary payment should include a copy of the most recent billing letter received by you from this division and should be mailed to the address shown on that letter. Your payment should also include your social security number and the tax year.
This is the partial payment policy for the Individual and Corporate Tax Division only. If you receive a notice from the Collection Services Division, you should pay the amount shown on the notice or contact that division immediately.