Revolver conversions I'd like to see

I've acquired a Dan Wesson 15-2, plain-vanilla medium-frame revolver with room for a 6-round cylinder of .357 Magnum.

The revolver was designed to allow the owner to switch barrels, from 2" to 4" or 6 or 8 or whatever.  The barrel itself is a tube threaded at both ends, and it rests in a shroud that can be vent-ribbed, full underlug, and so forth.  One end of the barrel threads into the frame, the other in a nut that in turn threads into the end of the shroud.  A special wrench gets at the nut, and a feeler gauge makes sure that you put the barrel back in with the right gap between breech end of the barrel, and the cylinder. 

The cylinder wouldn't be so hard to take out of the frame either. 

So why not a conversion kit, with 5-round .41 Mag cylinder, and replacement .41 barrel?