The repeater has several sections, separated with 2 vertical dividers that run left-to-right, leaving about a 1 to 1.5 inch gap at the bottom.
On the rear panel are the 2 antenna connectors (TX and RX), the external control connector (that I relocated internally), the power IEC C14 inlet, a circuit breaker for power protection, 2 fans thermostatically controlled by the power amplifier, and a blank panel under the fans for who-knows-what. I also added an ethernet bulkhead mounted connector.
The heat sink for the RF Power Amplifier makes up the rear-most space divider. The Power amp is directly attached to it, 10mW in and up to 100W out (adjusted to 50W thank you W4VSP). It also has a terminal block attached, for its power and the fan connection.
The front-most divider has the power supply and battery mounted on the back side, and the repeater RF deck and the Pi pHAT Stack setup mounted on the front side. There is also a couple of circuit breakers mounted on the right edge, for interrupting the DC flow if too much power is drawn. The top-down photo I have linked first does not show the battery mounted. I just realized I do not have any photos showing the battery mounted, or the STP ethernet cable mounted to the connector at the rear. I will correct that the next time I need to remove it from the rack for some purpose.