Attach USkeletalMeshComponent to Mesh in Character

I’m wanting to add a SkeletalMesh to my character following the few youtube tutorials that have a Blueprint character and have added the Skeleton with animation as the original source. Then have set it to hidden and have attached a new SkeletalMesh to the Parent Mesh to drive the animations from the AnimBlueprint using Retargeting Anime. EG https://www.youtube.com/watch?v=-VLQgFkZJiE

I have done the usual UPROPERTY in the .h file and in the .cpp file I have setup the CreateDefaultSubobject. But I am having errors connecting it to the default Mesh in ACharacter that is shown in the Blueprint. Is there a different way to attach the USkeletalMeshComponent to the default Mesh other than SkeletalMesh->SetupAttachment(Mesh);