My Thunderer is in .357 mag,though almost all the rest of my six guns are in .45...I did do the conversion, the pistola is a Pietta ,and you nailed it, it is the '61 Navy,fluted,which in real life only about a hundred were made.Pietta calls it a '62 Police,which it is not...the '62 was a five shot .36 built on a '49 pocket Navy frame,as Uberti correctly builds them.Anywho,I mated Cabelas Pietta Snubnose .36 with Cimmaron/Uberti's Thunderer...I call it my ''Puberti''.
The 'smithing was a little more involved than I'd hoped.The Gripframe and grip came already mated to each other,and finished,and I didn't want to disturb the finish,so,I had some work to do.The gripframe was some hundredths of an inch too large,but since I didn't want to mar the existing finish,rather than file down the frame flats,I padded my vise wth leather,and ''sqeezed'' the frame to fit.I then opened the hammer channel back up with a mill bastard file,finishing up with Swiss needle files.Because the Pietta revolver frame or ''reciever'' holes didn't quite match the holes in the grip frame,I had to move the grip frame holes a few thousandths forward to meet the holes in the revolver's frame.Out came the mill bastard again, dressing off the face of the grip and gripframe until they met the reciever squarely.That put the holes as close to lineing up as they were going to get.I then hoggered out each hole just a little to Accept the slightly larger Pietta grip frame to reciever screws,and reassembled the gun.Which was fine,but you could no longer draw the hammer back...the Hammer spring was now ever so slightly too long,from when I squared the grip frame to the pistol frame,so disasssemble,dremel,reassemble...and success!