When filing Ch 13 BK can I include arrearage in the total owed to my 1st lien (arrearage + unpaid balance)

Respectfully, you need to retain an attorney to represent you with a Chapter 13 filing. Less than 1% of debtors who file a Chapter 13 pro se will be granted a discharge. If you hope to strip a 2nd lien, it is even more important that you retain counsel. This is not a DIY project. Good luck.

Include arrears and unpaid principle balance and fees/costs when addressing each lienholder in your chapter 13 case. Motions to strip liens and treat as unsecured debt are not simple and frequently (even) bankruptcy attorneys run into challenges when attempting this, from correct service on lienholders to proving current fair market value, etc. You would be wise to consult with and seek representation from a competent bankruptcy lawyer. Do it yourself chapter 13 cases don't save you very much in the long run, particularly since a portion of attorney fees may be included in your case and paid over time.