To unlock some of the special features, I have to beat FF1 on both easy and hard. I played it on hard first, because at the time I didn't know that I had to play them twice to unlock everything, and I wanted to be as true as possible to the original Famicom version. Now I'm going to replay it at some point to unlock everything, but how do I do it?

I heard that you when you finish one version you have to save it's progress. I also found out when I tried to load my completed version it asked me for difficulty setting. Does this mean I have use my old save to start a new game, then save it on my old, completed file, or start a new game straight from the menu, and save it on a seperate file to get all the unlockables? Does it even matter?

I'm only asking because I want all my unlockables to be 100% complete, not because I particularly want to replay the game, and there's no way I'm replaying the game before I'm completely sure about this. I could have checked a lot of walkthroughs for this info, but the ones I have checked didn't explain this fully. Anybody who knows what to do?