Here's an update on the condition of the speakers:
Indeed, both tweeters are blown out. However, I see replacement tweeters for KG4s on eBay, so they can't be too terrible difficult to come by.
All four 8in woofers are operational and still make nice sound. Interestingly, the rubber part of the woofers is torn on the woofers of the right speaker, yet it appears someone repaired it with electrical tape.... and they sound just as good as the totally undamaged woofers! I'm impressed with that one. I'd remove the electrical tape and repair them properly but with them sounding just fine, I don't want to touch em.
All in all I'm impressed they sound as good as they do, I probably haven't used them for 5+ years.
So what do you guys think? Should I clean em up and eBay em? (speaking of which... I suppose shipping on these would be atrocious, hmm..)