This is part of New Payroll Item: "there is not a Pre or Post Tax to select from in the tax tracking section of the set up."
Yes, each time you add a New Payroll Item, you control it. You either use the EZ setup, or the Custom setup. I teach and use EZ, and also then Edit and step through the setup to confirm, refine, etc.
Example: Post Tax = New Deduction Item, set as NONE for Tax Tracking. This is Employee Deduction for health, wage garnishment, employer loan repayment, etc as Post-tax.
For Pre-tax, pay attention to the Tax tracking type, because that also updates the text you see for "this affects form 941, 940, box this, line that, and affects X, y and z and reports in the W2 box whatever with code whatever." Examples include 401(k) employee deduction with or without a company contribution match; 403(b); Health insurance; etc.