It's nice to have the right tool for the job. On the other hand, a heck of a lot can be done with the simplest tools.
A friend was arguing with me the other day regarding why he could not rebuild his '71 Harley FLH engine himself. "You gotta have a hundred different special tools!" he told me, "They show them all in the factory manual."
We had been having a little discussion of the relative merits of my RE vs. his Harley. He didn't seem too happy when I told him that I had just taken a 1999 Bullet all to pieces without even ONE special tool, not counting my Harbor Freight electric impact driver. Of course, things could have gone differently, I got lucky and everything was reasonably loose.
I'm also a big fan of KROIL, in my opinion, the BEST penetrating oil. This stuff compared to WD-40 is like Maker's Mark vs. Bud Light. Kano Labs will only ship to industrial addresses and you gotta sign a waiver saying it's for commercial / industrial use. Good Stuff!
http://www.kanolabs.com/ I also use a lot of their ExRust product.