I don't think that you need to be so fastidious about counting eye spots, though that is a good way to identify them. The violin shape on the cephalothorax (under part, near head) is pretty distinct and is very diagnostic of this species. If you sees that pattern, then you have a brown recluse. The large pedipalps (bulbous things near the head) and jaws are clear too. There are many good websites for photos.I particularly like spiders and brown recluse.

I hope this helps...and you should be sure they're dead before you mess with them!!

Where the person lives is a good clue. I'm pretty sure brown recluses only live in the midwest; there are extremely few in California, and those are only in the LA area (even though plenty of people will tell stories of brown recluses in their basements). There are 'violin spiders'(related to recluses) in other places, but they aren't really dangerous. I hope this helps.