I finally figured out what I wanted to do with my RXTX 6.3 so that it would be reasonably protected (considering the delicate coils and connectors) while suitable for display. I came up with a ready made 4x4 clear plastic box with the back side open (actually, I think this was supposed to be the top if the box had been used as a container as intended). The box came for a plastics specialty store on Canal
Street in NYC.
I built a strong subchassis, kind of a "shoe" that slides into the box out of reinforced PC material, with connectors on the back panel of the shoe. Photos should show what I mean. The black sausage like thingy is the I2C controller encased in heat shrink tubing.
As configured, I can slide the shoe out of the case in a flash, change BPF and PA/LP filter modules and thus change bands, without taking the case apart. All in all, it does what I wanted, and it looks pretty neat. BTW, it is actually connected and working throughout the photo session, WSPRing on 40m. There is an IN contest going on though, so I am not beaconing in these pictures, just listening, as I can hear a lot of QRP guys in the contest, working CW near 7.040. Pictures are under my call sign in the photos section.