Alright - so I moved the buttons around and tossed both on the back of the brake lever. It's much smaller than the original set of buttons I started with, so it looks MUCH better. It's definitely not "final" since I need to find out what material I will use to connect it to the lever. Right now I have both buttons stacked upon each other and slid into the back of the lever. When I did the ride Friday, the single button I had there was almost flat to the back of the lever. The buttons need to point straight out to the side. So, since I am about 5 Maker's Mark & Coke's into the evening, I cut up some rubber shim strips I had in the tool box (I needed something to fill the ~3mm of space from the back of the button to the inside surface of the carbon lever blade) to get the buttons to point in the right direction. The a proper dose of electrical tape got everything held into place. A quick ride up and down the street to check it out and I think that we are approaching the final prototype.
This should be close to the final ineration for me. I just need to get a piece of plastic I can Dremel into the right shape to connect the buttons to and fit inside the back of the lever blade. No rush on that though - I want to make sure that I have it exactly right first...


The left lever still has the original setup. Functionally perfect, but just way too big and bulky.

I will get the final wire splicing done later this week (hopefully) - I have to show you guys how I am attaching it to the harness - it's the cat's meow - and it'll be quick to switch to identical buttons on my aerobars. Way cool.
Also, the reason the left lever hasn't been updated is that I cut the cable from the Cateye buttons to their connector piece. Not sure why - I think my mind was just spinnin' and I had some idea in my head. That turned out to be a big mistake though as both wires had 2 wires inside, but only one had it's own plastic casing. The other was just a bare wire! Damnit! So I would have to splice the bare wires from both buttons together to connect to the negative wire on the harness. That's just an ugly that I didn't want to deal with. Now though - that bastard pair of buttons will get soldered to the connection piece (more on that later) and it'll be my bartop buttons for the rear derailleur on the road bars and the buttons by my brake lever for the rear derailleur on the TT setup. So all's not lost. I have another set of buttons arriving Monday. I should have ordered 3 sets though. 2 for the TT setup and an extra for the road setup. Damn. Now I have to order 1 more set. Double shipping charge. That sucks.
Do you know what doesn't suck though? The fact that I have Di2 and I get to use my beloved Campy 10s levers.

Have you ever wondered if there was more to life, other than being really, really, ridiculously good looking?