In the proverbial words of Charlie Brown, Uggggg. Ok still not terribly difficult, but you'll have to replace the fuse block on the univolt with something else if you replace the univolt.
Need a few parts, grit, spit, and a whole lotta duck tape.
Just helped a few guys get through this, take a look through this post;
http://www.airforums.com/forums/f37/...ck-135473.html , and this one
http://www.airforums.com/forums/f219...er-133233.html. They'll get your mind moving in the right direction.
Good news is that it looks like you've got some room to work with down there, and new converter is much smaller than the univolt.
Think you may recognize the fuse panel in the first post.