There are lots of great guides and 3D models to help you convert a Harbor Breeze solar light (https://www.lowes.com/pd/Harbor-Breeze-1-Watt-Black/5015598033) into a Meshtastic Node. If you are doing this with a RAK WisBlock system, this mount will help you keep your internals organized. I've included an INA219 current sensor in my design to monitor the solar charging so there is space for it on the mount. If you aren't using a INA219, you can just ignore those holes and it won't impact anything.  I've also included a plug for the power switch which I removed from my solar light. Putting in a plug seemed easier than filling it all with sealant. I glued the plug in with lots of E6000 since it seems to work for everything.

You will see two mount versions in this design. My favorite is the one that doesn't screw in. This mount just slips over the existing screw mounts and provides more internal headspace for wiring. The battery plug in particular is pretty high. If you really want to screw the mount to the housing, I've included a model called "RAK 4631 Mount Screw" which will attach using the existing screw mounts. If you do mount the board with screws, you can use the same screws that were originally in the Harbor Beach unit to attach the switch circuit board.

The prints should be easy. No supports are needed. Fill is pretty irrelevant since everything is so thin. I would use a reasonably tough filament though since the screws all make their own threads. I used PETG and it appears to work well. The WisBlock and INA219 mount holes are made to fit M2x4 screws. I'm not sure all four screws on each component are really required for stationary uses.

I've included the OpenScad files if you want to change anything.