I'll just close this out by saying the same thing; discuss with your attorney, or consult an accountant.
For personal expenses and deductions (mortgage, charities, medical), they can be divided in any way you agree. Generally, you would deduct them based on who paid the expenses. For example, if you are a member of a church and your ex is not, you would probably claim all the tithes as a deduction. You might split the mortgage 50/50, or based on your relative incomes. (In the year I separated from my wife, our income was 40/60 so that's how we split expenses.)
Business things might be split according to business activity. If the farm and mineral rents are from jointly owned land, that might be jointly split.
If you live in a community property state, there may be a legal requirement to split all pre-divorce income and expenses 50/50.
If you are at all unclear, or not in agreement with your ex, you really need professional representation.
