Residence tax issues

Hello,

This a multi part question, and we do not want to do at the employee level, we want to do this at the company default level.  We have over 12k employees and are in 49 states.  We are on E1 9.0

Our workbench has a JIT setting of 1

1. We want to stop performing "courtesy" withholding when an employee work tax area is less than their resident tax, withholding the difference at the resident level.

Basically we only want to withhold what is legally required, and nothing else (taking into account reciprocal agreements).  So just the work tax area, unless their is a legal reciprocal agreement between the states.