If I were to "shield" the uBitx, I'd first be shielding the various parts of the uBitx from each other.
For example, shield those high gain IF amps from the final amp.
Putting it all in a metal box can help if you have a lot of RF noisy stuff in the area.
Or if you care about some other gear hearing your BFO at 12mhz
or clk1 or clk2 or the 45mhz IF ...
I don't have either issue.