[Elecraft] KRX3 & K144XV question

[Alan Muldawer]

I have a K3 with the second receiver KRX3 and I also have the internal 2
meter card K144XV and what I would like to do is to be on 6 meter, VFO A
and to listen to 2 meters on VFO B . I have had no luck! It looks like in
the information for K144XV it seems that this is possible :  "If you have a
KRX3 sub receiver installed, you can tune HF-6 meters with the sub while
operating on 2 meters with the main receiver/transmitter. "
http://www.elecraft.com/manual/K144XV%20Data%20Sheet%20rev%204sm.pdf
I have separate antennas for both bands. The 6 meter antenna is on #2 and
the 2 meter antenna is on #3.
Has anyone been able to do this and how. Thanks!
73 Alan N3ALN