This will be slightly off topic as we didn't use 395's for steering, but to rotate our turret. We did this in both 2009 and 2012. We used the same approach both times with great success.
The basic configuration was a 395 driving a planetary transmission removed from a Globe motor. Globe motors were no longer legal for use and we had dozens of them sitting around.
Here is a little pictorial of how we interfaced them.
Notice the small aluminum sleeve between the motor shaft and the sun gear. That was the trickiest part to make. So, as you can imagine, these were quite simple to create.
Globe transmissions are approximately 90:1 reduction. These assemblies never even got warm after running tests and calibrations for hours.