Accessing Tracker UI elements in custom form

I have a very customized Tracker form wherein I need to access and disable form elements that angular is rendering. I know I can access the angular $scope of the form via
var myForm = document.querySelector(‘d2-custom-registration-form’);
$scope = angular.element(myForm).scope();

From there I can access the form values via $scope.selectedTei['UID'] but cannot access the form field itself. Normally I would access the angular model and flag the field as disabled, but I cannot figure out how to do it after DHIS2 does all the rendering. Thoughts (other than using jQuery)?