how do I handle duplicates after unifying or merging my Aperture and iPhoto libraries?

I'm asking in multiple forums on the web but here's the situation...

I decided to merge / unify my Aperture library (124.xx GB) and iPhoto library (165.xx GB). The job required a fresh 1 TB external drive onto which I copied both libraries after they were updated with their respective latest version native applications. I opened the Aperture library and imported the iPhoto library. After 2 days of processing, yes, two days for nearly 60,000 combined photos on a 2007 iMac 24" processor with rebuilt previews, I was able to control Aperture again. Upon quiting so the unified library could close properly, I found a 343.xx GB unified Aperture library ... nearly 57 GB larger than the two sources!

OK, I have been known to process photos in Aperture, export a batch from a project, and import them as a new event in iPhoto so my wife and family can access the best images. But, I'm surprised at the size of the overage. So, I'm left with a feeling of

(a) a wasted 2 days ... continue using the separate libraries,

(b) searching the web for a "duplication finding" program that works with unified Aperture/iPhoto library structure (good luck!), or

(c) time to brew some coffee because I'll be sorting one-by-one through the Photos tab to delete duplicates.

In the case of (c), I have a delimma as well. Namely, how do I convince myself of "what" exactly I'm deleting from what "appears" to be duplicate photos. In other words, how do I determine if a photo is

• a Master (now original) file from Aperture,
• an edited version of a Master (now original) file from Aperture,
• an original file from iPhoto, or
• an edited file from iPhoto.

Depending on the exact nature of the file, I might choose to delete any work from iPhoto in favor of keeping the Master/original or edited Master/originals from Aperture's original library before the unification.

Any suggestions from others who already faced this dark reality is GREATLY appreciated! Thanks in advance.