Using SV_InstanceID to retrieve the instanceID

Is it possible to use SV_InstanceID to retrieve the instanceID for a standard Instance Static Mesh in a shader?

By default it seems to only be included if MANUAL_VERTEX_FETCH is enabled… what is MANUAL_VERTEX_FETCH and how to enable?

I have been packing the instance id in the w-component of the instance transform and while it works, it seems less than optimal.

Thanks for any feedback/advice

[Update] I was able to get this to work by changing 2 lines in LocalVertexFactory.ush: