Remove units from a Froce10 MXL's stack

We a have a stack of 4 Froce10 MXL switches with OS 9.14(1.9P4) via the 40GB in a daisy chained ring configuration. We need to remove the last two switches in the stack (unit 2&3 in inv) but we noticed that the management and standby are currently on unit 2 & 3.

If we shutdown 2 & 3 will this cause unit 0 & 1 to go down, lose connectivity, etc. If not will unit 0 &1 become the management and standby without them restarting? Unit 0 and & 1 are running ISCSI traffic and we can’t risk the outage.

Other thing that I am concerned about is the ethernet port getting renumbered. I am not sure how the OS knows what unit to assign the port numbers. Is this based on the unit mac address of the individual switch's?