I decided to start a thread to document the work on my Rack mount spacecraft parts concept. the rack mount units would be usable for making probes, or inside avionics bays in larger spacecraft. I plan to add parts for smartparts and KOS as well   4U Fuel Tanks: These reuse existing textures for the tanks themselves to lower memory usage   Probe core and SAS: A little PCB model I'll find a use for eventually:   To follow development on Github