That is not necessary. The rules are clear and the taxes are either dischargeable or they are not. Trust fund taxes are not dischargeable under any circumstances and income taxes are subject to the rules you mentioned. If there is a federal tax lien in place, bankruptcy will not be able to remove it.
THESE COMMENTS ARE NOT LEGAL ADVICE. They are provided for informational purposes only. Actual legal advice can only be provided after consultation by an attorney licensed in your jurisdiction. Answering this question does not create an attorney-client relationship or otherwise require further consultation.
Usually the Internal Revenue Service themselves will make a determination whether or not the taxes are dischargable. You should contact the 'Special Procedures' department of the IRS in your district to determine how they stand on your particular case. If they determine that the debt is dischargable, attempt to get a letter to verify.
If they determine that it is not dischargable and you disagree with their analysis, bring the adversary.
Where you list dischargeable taxes is based on attorney practice. Some, like me, list them on Schedule E. The amount of priority is noted on that schedule. As for the taxes themselves, either they are or are not dischargeable. Have your client contact the taxing authority before or after the case is filed for a determination. If you do not agree, ask for documentation. There is no need for an AP.
[This communication is intended as general information and not specific legal advice, and this communication does not create an attorney-client relationship.]