Find a gunsmith and ask to be shown how.
it is a little less powerful but not by much
Yes you can. The bore is the same size.
50-400 usd
Not in .38 Special. Several manufacturers make handguns in .38 Super, though.
No. Only use what is stamped on the barrel.
Impossible to say without a more detailed description of the handgun in question.
No, i asume you dont have see .380 pistol and a revolver 38 spl, the .380 and 38 spl ammo share de same diameter boot no the longer, the 38 is for a 38 special revolver tipe and the .380 is for an automatic pistol tipe some people call 9mm short.
100-400 USD depending on condition.
Library, Blue Book of Gun Values, Standard Firearms Dictionary.
I'm not real familiar with the 38-40, but based on what I looked up, I'm going to say no. The 38-40 cartridge uses a .40 caliber bullet, which means the chamber in a 38-40 handgun would be too large in diameter to properly/safely hold the .38 special.
10-10000 USD depending on specifics, history, accessories, engraving, etc..
Model numbers were not used before @ 1957.