Cheap tweak from Virtual Dynamics:

Apparently this Fat Wrench is offered in a couple of versions. Here is a site where the model shows 5-60 lbs. I don't think the differenc ebetween 8 and 10 lbs. would be that dramatic. Chances are if you manually tightened the screws down it would be more than even the 10 lbs. so you should be fine.

http://www.amazon.com/Wheeler-553-556-Wrench-Variable-Torque/dp/rebates/B000Q2AYF8

I think you'll be fine. I just did a torque test on one of the original screws on one of the midwoofers and it was about 10 lbs. Actually, I pre-tested all four screws on a mid-woofer driver and all four were slightly different. Hmmmm... interesting. Also, a correction: it is inch-lbs. not ft.-lbs. Even if you don't hear a dramatic difference, you can always use the Fat Wrench for your hunting and target rifles. Or if you don't hunt or shoot, it would make a great gift for a relative who does. (O: Let's have some fun.

Might as well make sure the screws stay torqued too.
http://www.threadlockers.com/vibratite.jsp

I torque screws on my spring guns (pellet guns), and use vibratite to ensure they stay put. One of the nice features of Vibratite as a thread locker is that the screw can be removed and inserted several times before it needs retreated.