First, in regard to trying to reshaft a persimmon, there is only one reason to do so: you intend to play the club. The inherent issues in reshafting and re-boring a persimmon likely will diminish, greatly, any collectible appeal. In that regard, if you are patient and have the right tools, you can put nearly any modern shaft into an old persimmon. I would recommend a drill press (even a cheap one) and a rig that will hold the hosel at a 90 degree angle (GolfWorks, etc have various options). Tape the hosel to protect against cracking. You likely will lose a little of the hosel as you match it up to the diameter of a new ferrule. You may find it easier to trim a little off the hosel first. Again, be patient and keep the hosel taped to prevent cracking. Once you re-bore the hosel to .355 you are good to go. Some liberal use of epoxy can help fill in gaps and imperfections where the hosel and ferrule come together. Gently sand this area smooth. Again patience. Certainly pay attention to matters of swing weighting and length. If you aren't comfortable with general club building and fitting, you will end up ruining the club and your enjoyment of it.
I have done this several times to bring an old club into the modern game, and the results have been mostly successful (a couple of cracked necks thanks to my own impatience). Remember, if you reshaft with a non-metal shaft, you can't anchor it with a screw in the hosel (can undermine the integrity of the shaft), but I have yet to have a head come loose with any modern epoxy.
Second, as to the warning that such effort is fruitless, that persimmon puts you at a huge disadvantage, I disagree. Like most things golf, it is a balancing act. While I have only one persimmon in my bag these days (finally yielding to a modern driver a year ago), I don't carry it to be nostalgic; I carry it to be competitive. The great downside of persimmon is the inability to practice with it - the rock hard range balls do a number on the polyurethane and the clubface if not careful. However, the immense feedback from a solid block of wood, means you don't have to practice as much. Hitting a modern driver, I might as well shoot Novacaine into my hands. Thankfully the physics tend to balance out - it is hard to hit a really bad shot with modern driver. However, by the same token, it is hard to hit a really great golf shot with one too. That's not say you don't get good drives, but the ability to work the ball with persimmon is a wonderful art that is worth preserving. While I also like the idea of preserving these beautiful old woods, I would much rather see a persimmon in the bag than in the case, as they say.