The MMPI-2 is available on the "Forbidden Knowledge" Tor Hidden Service:
http://65b6ro3kmuuj4wvpqnepmk3y54eindlsuctixsovqpoz6x3yan7cxgid.onion
To view this site and take the MMPI-2 online, you will need to use the free Tor Browser, which you can download here:
https://www.torproject.org/download/