Okay, I just wanted to give an update.
I asked the question on the Microchip forums and got an answer about an hour later.
birdman0_o, this is mainly for you, but it's for anyone else who was having the problem, as well
After installing the compiler, you need to open MPLAB X. Go to "Tools" and select "options". Go to the "embedded" tab, and click on the button that says "Scan for Build Tools". The compilers should appear in the "Toolchain" window.
So, the whole path is Tools->Options->Embedded->"Scan for Build Tools".
This worked for me, and I hope that it will solve your problem as well, birdman.
Good luck, and thanks for all the help!
Regards,
Der Strom