Squeal's definitely the throw-out bearing - cables don't squeal. A squeal combined with increased pedal effort might indicate the TOB is getting bound up on the bearing retainer. If you've got the stock aluminum bearing retainer on there, that's probably what's going on. When you pull the tranny to do the TOB (and clutch/flywheel, presumably), that'd be a perfect time to upgrade to an FRPP steel bearing retainer - it's a whole four bolts and a bit of RTV, not even a challenge. Just don't overtighten/strip any of those four little 10mm bolts, or you'll be slobbering tranny fluid onto your new clutch.