Didn't see this answered here

I do truly apologize if there is a Tutorial on this, but I didn't see one. I'm simply attempting to make a sound set for a unit. I saw someone who used a 'Selection' based trigger system, but think that's pretty rediculous(In the sense there has to be a better way). Do I just copy over the old sound files for a unit, or do I need to make a custom unit, or what?

I figured this out, let me share what I found: You can replace the sounds in a sound pack, but it's a little tricky. First off, do NOT import the sound you want to replace it with. Right click on the sound in the sound editor you wish replaced, and select 'replace internal sound'. It will bring up the file selection menu, find your file, and select it. If you want to change it to something else, you will need to remove the sound (It will be listed down in the 'imported' section, in the normal folder for where that sound would be).

Yes, I'll be doing a tutorial for this someday - it's asked a lot (and I'm sick of answering ;)).

Giving a unit new sounds is the same as replacing a units sounds as you would any file - just go to File Manager, import the sounds that are named the same and set their directory to the same. e.g. (from the top of my head) units\orc\grunt\what01.wav.
I'll have to check your method above, as I've forgotten it.