Need help with PAT0 editing to change some stage icons.

[Xenozoa425]

I understand how PAT0 works in general, that each texture in MiscData[80] (where I'm currently working on) is assigned a certain number, and that number corresponds to a specific stage (i.e. MenSelchrMark.20 is the SSB icon that goes over BF and FD). What I'm trying to do is change the MenSelchr and MenSelmap marks for some stages, but every time I try to change one icon to another (such as changing one Mario icon from MenSelchrMark.01 to MenSelchrMark.02, the DK icon), it screws up the order of everything when I save it and open it back up. In game, everything is jumbled up, and looks like a huge mess.

How do I go about fixing this? I've looked all around the internet, and I can't find anything that helps me. Not even a simple tutorial.