gistfile1.cs

// SomeClass is stored as typeof in a var

Func<SomeClass> factory = () => Container.GetInstance<SomeClass>();
Container.Register<Lazy<SomeClass>>(() => new Lazy<SomeClass>(factory));

gistfile2.cs

var lazy = typeof(Lazy<>).MakeGenericType(type);
var method = typeof(SimpleInjectorExtensions).GetTypeInfo().GetDeclaredMethod("RegisterLazy").MakeGenericMethod(lazy);
method.Invoke(container, new object[] {container });