Replacing Gen5 with Gen6 in active cluster

We have a client that has two:RecoverPoint Gen5 clusters running 5.1 (VNX).  We will be replacing one side with new storage and Gen6 appliances.  That will require a teardown of the environment and redeployment. The other side will keep its storage, and get new Gen6 appliances.  I believe we should be able to add the Gen6 appliances to the existing cluster, move the replication to the new appliances, and then remove the Gen5 appliances from the cluster.   We can't get the solution generator to come up with a step-wise procedure, but it seems like it should work.  Does this sound reasonable?