Access StackLayout in platform PageRenderer?

I'm using a custom PageRenderer to add some native stuff to a Page. I have the page setup in the PCL (Forms) project with an image and a StackLayout. Is there a way I can access the StackLayout and add a UIView to it (in the platform code)? I know I can simply add the UIView to the subview:

ViewController.View.Subviews[0].Subviews[1].AddSubview(_myView)

...but the positioning doesn't work in this manner.

I can always position it in the platform code...assuming I do this via _myView.Frame = new CGRect(...)

Thanks for the help