Forge Viewer in PowerBi load and unload a model.

I am currently using a tutorial I found to put the Forge Viewer into PowerBi. And in this the URN is hard coded into the script. What i want to do next, now that i have the viewer working in PowerBi, is be able to load and unload a model based on the list of models that i have.

Currently in PowerBi i have a list of my model that i have along with their URN's. I want to be able to click on this list that is in PowerBi and update my Forge Viewer. So far what I've added is code to unload a model, now i just need to find a way to load another model dynamically. This is what i have for unloading a model that i have add to the visual.ts file.

         this.forge_viewer.unloadDocumentNode = function (manifestNode){
         //if model is in memory, just unload it.

         let model = this.impl.findModel(manifestNode, true);
         if (model){
             this.impl.unloadModel(model);
             return true;
         }
     }

 Can someone guide me in the right direction or show me how to load a model in the way i decscribed above? if that isnt possible would there be another way?

Thank you in advance.