I got it going! Thanks to some help in another thread, I got my snes9x TYL 0.4.2 Working!
First, you need a Fat PSP for this.
Download the 1.50 Add-On for your Firmware from
Here
Second, Download the 1.50 Eboot file from
Here
Now, Rename the 1.50 Eboot file "150.PBP" and put it inb the root of your memory stick
Next, inside the zip for the 1.50 add-on, there should be a folder. Copy this folder to PSP>GAME and then run it. You'll see alot of text going down the screen if you did it right, or an error if not. Yay!