Looks like you have a good start. My son has the same tank over 4 years now. His fans are shot I think they finally died last week. I would be interested in seeing your fan mod. I've been icing the tank every day to keep it at 80 degrees so I definitely need to replace the fans.
I would post a eBay link where I got my fans from but I think that is aginst the forum rules these days; however, if you search:
NEW Ultimate Oceanic Biocube 8 & 14 dual Fan upgrade Kit Plug Play BALL BEARINGS
in eBay you should find that I bought for under $30.
The fans are quite loud but they do not rattle like the stock ones did. I would take a picture of the wiriing but all my wiring is modded and would probably do you no good. No worries though because the fans are super easy to install. All you have to do is plug and play.