Remove Principle Swich and make Subordinate as Principle (CISCO MDS)

Hi Friends,

I need your help to remove legacy Switches in my Environment .

First Let me explain you my environment and what i would like to do.

We have 4 CISCO MDS Switches. Switch A, Switch B, Switch C and Switch D

Switch A and Switch C are connected via ISL, in same way Switch B bad Switch D are connected via ISL.

Switch A and Switch B are principle switches and Switch C and Switch D are subordinate Switches. Recent past we have done few server decommissions which are connected to Switch A and Switch B , Now only 2 servers are connected to those switches and one Legacy EMC Clarrion storage is connected.

So now my plan is to remove Swicth A and Switch B from my environment and connect 2 servers and EMC Clarion to  Switch C and Switch D(Suborinate) and make them Priniple Switches,

Can someone please provide me the plan and suggestions to do this!!! Thank you very much in advance!!