So i posted a message about my rear diff leaking and not knowing why a little while ago and came to the conclusion that its either the gasket or a cracked something. I still havent fixed it and it leaks about so i can barely touch it with my pinkey in the hole in a little more than a week. So far ive just been fillin it up every once in a while.

Now comes the question wether i should fix it now or save some money and get tires, gears, and a lift all at once? I got an 87 Runner. Voice your opinions, also suggest what the leak may be, and how hard it is to do gears.
Thanks, Alex