I've circled back and tested my pin straightening fix for the pwm controlled cooling fan. Unbelievably, my fix worked, the pins were soo tiny I was sweating it! The fan is now PWM controlled so it modulates speed as needed, this addresses my outstanding Pi cooling concern. 

I've also been testing ADS-B tracking and SDR++ with an RTL-SDR module and I started off pretty impressed but over the course of the last month or two, ADS tracking seems to be glitching out. The RTL-SDR gets super hot so I am going to add a heat sink but it also could be my USB hat which seems to be somewhat unstable. I've also noticed my SSD disconnects with the slightest jarring of the usb cable so something going on there that will need to be hardened if this thing is supposed to be field ready.

I often find myself going back in my mind and reconsidering the original shielding and hardening requirements I started with. I also think about my abandoned efforts using the emf cloth and copper foil as an improvised shielding and as I think about how I could do better, I started to think about steel mesh products and how it could be both a rigid frame structure and shielding. Ran some numbers and realized the mesh structure needs to be pretty tight but if you layer different mesh types you can adjust the protection bandwidth. Going a step further, I found a steel product that is manufactured as a 5 layer sheet with this same concept and I believe I am re-converging on a potentially new solution, may not be for this project but something that's got me thinking.

Next Steps: update ADS B software. reposition ADS-B antenna, retest under load, observe thermal behavior, scrounge up a used heat sink to attach to RTL-SDR unit. retest with heat sink, compare and assess