Fingers Any special mods.need to be done to an 1858 Pietta.
Mike, I know you asked Fingers but I'd like to add my 2 cents.
"Special mods" are plenty but I'd not bother with any until you are sure of a few things first. Such as what "style" you want to shoot. For example, shooting "Gunfighter" style requires you to have a gun in each paw and work the hammer and trigger with only one hand. Whereas, "Cowboy" or "49er (us older Cowboys) can shoot one gun at a time and hold it with both paws working the hammer quickly with the off hand. Mods for these guns might be different for you than for me or none at all.
I like my Dragoons but loading powder and ball between stages can get hectic. Each shooter is expected to pull line duty in some form such as scoring, brass pick up, load table monitor, unloading table monitor and so on. Sometimes if there are not enough people, you hardly get time to grab cartridges ready. Black powder pistols are allowed to be loaded away from the loading table and then capped at the table but it takes more time. So, a Cartridge Conversion for my Dragoons was a great "Mod" for my pistols.
My Rugers I shoot stock, just lighted the hammer spring a tad is all I've done with them.
Rifle Mods involve replacing plastic followers with brass or other metal after market followers. Lifter kits, short stroke kits and safety button plugs are all available.
Gun Smith work can easily cost you both arms and legs if it gets away from you. I haven't done anything to any of my rifles or shotguns other than slick up the chambers of my SxS coach guns so the spent shells fall out easier.
Mods can wait until later. Unless you can get a deal on guns that have already been modified. In which case I would look VERY hard at WHY the gun is for sale...