Thanks for the replies. You all are great. Some replies from me:

One last question (for now). Do I use Thread-Lock on the hard drive screws? Or is that some kind of taboo electrical risk or something?

simspos: Thanks for the tip. I was about to go buy some Loctite in the next 30 minutes. I would have got the wrong stuff if not for you.

mrfixit: So, blue Thread-Lock brand compound? I'll see if I can get some. I hope the container is blue or something. I don't want to stand in the store and spray the stuff on my fingers to find out it's blue.
And yeah, I'll try some screws from a power supply. Haha, those old AT supplies ARE good for something after all!

csf: Yeah, my stock washers are doubled up too. They are SO thin though. 1/2mm?

decay: Wow, bold. So between csf's thin washers and your NO washers, I should be set.

Ok, I'm doing the upgrade tonight. Wish me luck!