ROS + gazebo + PX4 SITL install and configuration

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Hi, I'm trying to put a simulation together using ROS (currently Kinetic), Gazebo and PX4 SITL. At the moment I'm going round in circles a bit, and I've tried a few different approaches:

1. PX4 + Gazebo (via Github PX4/Firmware repository). I can get a quadcopter up and running via PX4. I have run a few tutorials, and I have offboard control running via mavlink. But I can't get ROS to run - certainly the ROS launch files don't run under roslaunch - it claims that the px4 package doesn't exist. Abit or googling and reading around tells me that the reason is that I need to start gazebo out of ros to get a ros interface working.
2. ROS (Kinetic) running ros_gazebo. Again, I can get this up and running, and use roslaunch to get my world up and running in gazebo. But it looks like I don't have an instance of the PX4 mavros autopilot running - none of the mavros command line tools work (mavsafety, mavcmdetc), and rostopic show me that the only publisher or subscriber to the mavros channels (e.g. /mavros/global_position/global) is mavros.
3. Going back to PIX4 and ggogling further and I read that a ROS Kinetic interface is not supported by Gazebo, and I need to roll back to ROS Indigo. But ROS Indigo is not supported on Ubuntu 16.04 (Xenial) .. so I would need to install an earlier Ubuntu via docker...

at the moment my code structure is roughly as follows:

• /opt/ros/kinetc -> ROS Kinetic installation
• /home/steve/src/Firmware -> clone of PX4/Firmware from Github. enables me to run a model via make posix gazebo
• /home/steve/src/uav_inspection_ws -> my catkin workspace, with my own packages (e.g. offboard control for PX4 tutorial, etc))

Before I go any further down a rabbit-hole, I'm wondering whether anyone can set me on the right path.

Many thanks

Steve