Install AMG to Lens
Lay the PCB of the sensor over the standoffs on the camera lens cover. Turn it over and see if the lens of the sensor lines up with the small hole in the cover. Rotate to orient the PCB so it's centered with the hole.
Secure Sensor to Mount
While holding the PCB onto the lens cover, insert four of the M2.5 x 5mm machine screws to the mounting holes and fasten until fully tightened.
The 500mAh lipo battery can be directly plugged into the female JST connector on the Adafruit Feather HUZZAH32 board.
Install Switch to Cover
The on/off switch can be press fitted into the little housing on the side of the back cover part. It should be able to snap in at an angle and held in place with friction.
The TFT FeatherWing features mounting holes on each corner and will be secured to the back cover part of the case with four M2.5 x 5mm machine screws.
Place the PCB of display over the four standoffs and flip the assembly over to see if the screen cut is properly lined up. Orient the display so they're correctly positioned. Insert and fasten four M2.5 x 5mm machine screws into the mounting holes.
Mounting The Battery
The 500mAh lipo battery can be secured to the back of the TFT display with a bit of mounting tack. Just make sure it's not touching the reset button.
I would rerouting the cable of the battery in between the Feather and TFT display. Also make sure the battery isn't able to actuate the reset button, or else bad things can happen!
The orientation of the thermal camera sensor and the display need to be setup correctly before installing the circuit into the camera body. Play around with the arrangement to determine the correct orientation of the components.
Install Camera Sensor to Lens
Now that you got a firm understanding of the orientation, press fit the lens cover through the back of the camera lens frame. You'll need to determine which way is up, down, left and right.