@Eric EnglandUntil Hortonworks supports Nifi 1.4 and publishes a new management pack for the new version, your only option is to create your own management pack. One way Hortonworks provide value to its Enterprise customers is to make sure that all parts of a version are tested together - integration testing. If you upgrade one component from let's say HDF 3.0 then that creates a risk from support stand point. Since everything Hortonworks does is open source, you can just create your own management pack and manage new version of Nifi from Ambari.
https://cwiki.apache.org/confluence/display/AMBARI/Management+Packs -->how to create management pack.