According to wikipedia on RKCB, after an 03 or 14 response
...the 4NT bidder may ask about [the queen] using the cheapest bid other than five of the trump suit. The code for replies to that "queen ask" vary; a common rule is that the cheapest bid in the trump suit denies the queen or extra length and any other call shows it.
Sometimes though, a call of 5NT is only available to show the queen (Example: 1S - 4NT - 4D - 4H --> 5NT - shows the queen). So now assume I find out we have together all 5 keycards and the queen, so now how do I ask for kings? Is there a standard simple non-nonsense way that most casual/random partnerships use? (5NT that I'd use to ask for kings is wasted ...). I'd assume that would be now bidding: 6C (and responses to it 6D - 0 kings, 6H - 1 king, 6S - 2 kings, 6NT - 3 kings). Right? (P.S. I'm looking for most simple straight-forward non-nonsense common way here...
In other words, how do I ask for kings in RKCB (as opposed to regular Blackwood)? (since 5NT is now occupied by queen ask)