The standard deduction will be split between you so you won't be able to change that.

A short excerpt from the instructions:  Line 15. If you used the standard deduction on your joint tax return, enter in both columns (b) and (c) one-half of the basic standard deduction shown in column (a).

For assistance here are some helpful tips for the injured spouse.

• Reminders & Tips:  

1. If the injured spouse is the only one with income all of the refund will be released after IRS review of the Form 8379.  
2. If there is income from both spouses, the IRS will apportion the refund and some will be released.
3. If the injured spouse had no income, the refund will not be released and the form should not be filed.
4. If you are not in a community property state, and both of you have income, you can divide exemptions up any way you see fit. It is possible the IRS may make some adjustments based on the income levels for each of you.  Let them do that when they receive it.  
5. If you do live in a community property state, community income would be split equally between the two spouses.  With respect to deductions, the deductions would be split depending on whether the expenses related to community income or separate income.
6. The standard deduction must be split between you so you can't change that part. 
7. Per the IRS, 11 weeks for an e-filed return and 14 weeks for a mailed return.
   
8. Review the screenshot attached for the initial important answers.