Done it on 4 headsets now, couple of DC and couple of Peltors.
The DC headsets are a piece of cake-----------just follow the instructions and you will be fine.
Dont forget the foam insert that fits over the speaker area, you can get feedback without it.
I used the battery boxes for a few years on the old Stinson, in the RV, I used the power supply they sell to panel mount the power jack, and got rid of the battery box. One power module will power two headsets.