opening / modding Moto V300?

I'd like to upgrade the memory in my V300 (I believe it's not under warranty, and I think I should be able to get a memory chip MUCH cheaper than I could get another phone with the same amount of memory I'd like to install.)

Does anyone know how I can find out how to do this? I have some experience digging into electronics.
I'd like to install at LEAST 128MB or 256MB of flash. 5MB isn't NEARLY enough for the mp3 files (full-length songs - about 8-10 hours worth or so) I'd like to put on my phone.
Also, does anyone have any tips on how I can get my homemade ringtones to be as loud as the ones that come with the phone? I maximized the volume of the songs to their maximum-before-clipping volume, and they still appear much quieter than the ones that are already on the phone. Do I need to apply some dynamic range compression, re-normalize the volume to -0.1dB, then re-transfer the songs to the phone?
Or, is there a way I could make the built-in speaker louder?
Also, is it possible to make it so I can plug in the phone, and have it act as a USB thumb drive, making it simpler to transfer files to/from the phone? I need to be able to do this esp. at a library, where they won't let me install custom drivers.