Self employed

Amy,

I said we, because we are husband and wife who were in partnership.   We withdrew one member out of LLC and going forward will be filing business income on a schedule C with individual joint taxes return due to now being a single member LLC.  My husband has a regular job and has a W2.  We are in Minnesota and not in a community property state.  Due to business structure now being a single member LLC, we, husband and wife, will be filing a joint individual 1040 and doing the business aspect of taxes on a schedule C.  Should we use the EIN or my social security number for estimated taxes since I remain in the single member LLC?  Or would you still say I should do estimated tax under my social security number?  I just want to do things correctly. 

Thank you kindly