jeffd:
Making some progress here... for what I've read I can use another Arduino to burn the bootloader using ISP, but in order to upload a sketch and overwrite the bootloader I would need to use an ICSP programmer. Is that correct? If I can use another Arduino to burn the bootloader can I also use it to burn a modified bootloader?
ISP and ISCP are pretty much interchangeable. If you can burn the boot loader you can burn a sketch there really is no difference.