GRC USRP2 Clock Source

Hello,
In GRC is the USRP2 Clock Source parameter implemented? I have tested
it with the three options and the top block.py file changes accordingly,
self.usrp2.source.xxxx_0.config_mimo(usrp2.[don’t lock / lock to mimo /
lock to sma]). However, when running with no mimo cable or external ref
and either of those two selected as the clock source my code executes
fine as if it was on “don’t lock”.

So, am I incorrectly interpreting what you do to set the master clock of
the system or is it not yet implemented?

Thanks,
Bryan