Answering my own question here...
For me the 404 problem solved by building from source and accounting for the required dependencies using a maven plugin. Previously, I was attempting to use the prebuilt binaries and lib/ depedencies.
I built the modules from source (2.18.3) and modified the file maven file to copy the dependencies to the target folder, which I then copied to WEB-INF/lib.
Here is the pom file addition I made to get the dependencies.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.8</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>prepare-package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/classes/lib</outputDirectory>
<includeScope>runtime</includeScope>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
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