This is usually within the standard views. In the Orion Summary Home, you have a node list of all monitored switches, routers, servers, etc that you are monitoring. When you select any of these, you'll be taken to the Node Details page. On there is a custom object chart or multi-series chart. You can edit this and choose all interfaces on the node, and choose inbound utilization. You'd then click submit. To get outbound utilization, you'd go to customize page (on the top right), in the next page click the + on column 2, add a similar chart as you just configured, move it up under the first chart with the arrows on the column, click submit, then edit that chart and use the same selection for interfaces specific to the node, and use outbound utilization. Unfortunately in NPM currently you have to use 2 charts to do this.
Worked great, sadly I had the business requirements wrong. Gonna start a new thread.