Upgrade existing 100D to 100E in FortiManager

I have an existing Fortimanager-VM with 7 locations, all using -D model Fortigates.  We just upgraded our first location to a 100-E HA-pair from a 100D.  I just tried to do the RMA device replacement command set that support gave me and it fails because it only works for like model to model replacement.  I don't want to add this as a new site because we used Fortimanager to configure a VPN-mesh across all 7 sites and I am worried the push of the update back to the other 6 locations will crash the mesh.

Is there any way to replace the 100-D with the 100-E HA pair in FortiManager?

Thanks,

Bob