Did a deal for this a couple weeks ago and can now post a couple pics of it. I had seen this gun sell on Gunbroker quite a while back (at least three years ago). The owner was only about an hour away from me at the time. I didn't have the inclination to spend the money on it then. Had I known I would buy it a few years later for 40% more than it sold for then, I might have reconsidered....
K404 is the only #5 so far known that was built with a birdshead grip frame. This gun confirmed something I had suspected for several months now - that Grover used assembly numbers on his parts during at least one production period. On some guns, you find only serial numbered parts. On this one and another I own, parts that are often serial numbered, like the cylinder, triggerguard, and backstrap, have matching assembly numbers instead, but no serial number. I've even seen assembly numbered lock work on one gun.
I doubt I'll shoot this one, as I've never been a fan of a birdshead grip frame on a gun with any kind of recoil. However, this gun is worth having to show that Bill Grover would build just about anything special order.
Enjoy!