I agree too to your objections to that Simmons 2.5x bamboo scope! I had reasons for using it: Mounting a regular eye relief scope like a Zielklein on a hammer double is a bum idea IMHO. Either you mount it too high for fast use or it blocks access to the left hammer. I have never seen a Noske here in Germany. I thought I needed a low mounted, longer eye relief scope so the ocular end is forward of the hammers. Granted, a Voigtlaender Skopar D 3x like the one on my Haenel 1900 would have been better, but 18 years ago I did not even know such a thing existed.
http://i1018.photobucket.com/albums/af303/kuduae/1900mSkoparD2.jpg
That Simmons was the only such scope available to me then, and the Warne mounts were the lowest qd mounts with the least obvious bases I could think of. Properly fitting another scope would require different mounts with windage adjustment and bases in different positions. As I believe in "Never repair anything that works", the less than perfect setup remained to this day.
This is rather a topic for the gunsmithing forum, but as you asked:
I made and fitted a larger hinge pin to tighten the action.
When the rifle came my way the muzzles looked like the thing was stored muzzle-down in a flooded room. so the useless part of the barrels had to go. I cut off the barrels and recrowned them. Next I developed a load with proper ballistics that gave acceptable individual groups. Then I made a makeshift adjusting clamp for the muzzles, filed a new regulating wedge, wound barrels and ribs with wire and so on, resoldered and adjusted the forward third of the barrels. Next time at the range, I shot a right-left 6 shot group. Repeated the process 3 times until both barrels shot together at 100meters. Last, I rust blued the barrels. Getting the rifle to full using condition took the better part of a year. Regulating a double is neither a lost art nor a trade secret, but merely a tedious and sometimes frustrating game of patience!I myself have reregulated 11 doubles by now, 5 by resoldering and 6 by load development.