Gotcha 
const view = [...window.__client.page.views._data.values()].find(view => view.value.mountPath == this.parentNode.parentNode.getAttributeNode('data-component-path').value.split('.')[0]).value;
you can than do things like view.custom.read('yourprop'), view.custom.write('yourprop', thevalue), view.props.write('yourprop', thevalue), view.params.read('key')
you could dig into the children/root too, but you should probably just use bindings to the custom props unless you know what you are doing 