Seriously, skip out on all of the pre-BC instances (the ones that come after Sunken Temple, I'd say). They're almost a complete waste of time. Once you're high enough to do Scholomance, Stratholme or Lower/Upper Blackrock Spire, you should be at least close to high enough to be questing in Hellfire Peninsula.
To demonstrate how useless items from pre-BC instances near level 58 are, here's a plate chest piece from an easily solo-able quest:
http://www.wowhead.com/?item=28055Here's the Lightforge chest armor:
http://www.wowhead.com/?item=16726Your gear gets replaced so fast while questing in outlands, it makes any effort to "prepare" for questing there a waste of time.
Of course, if you want to do it for enjoyment or novelties' sake, ignore everything I've said.
