How is this story unfolding? I ask because I am in the market for a new CX bike.
Sorry about the delay on this, but here's an update. I placed the order with the shop a little over 2 weeks ago and it took about 2 weeks to get the adapter in. My initial measurement of the adapter is about 11mm tall, but it has a section of it beveled out on the inside to accommodate the angle of the lower bearing (so that they sandwich together nicely).
With the adapter and bearing in the headtube I was still 3mm short of making good contact with the crown race. The only solution at this point is to use a small spacer under the crown race to make it work. Normally I wouldn't do it, but 3mm isn't very much (especially given how much of this particular fork is tapered) and I am using good aluminum.
The next issue is finding a washer that will work. We thought about it for a while and ended up cutting off a piece of the crown race setting tool to actually make it work. It had the perfect inner and outer diameter and is really good anodized aluminum. It took quite a few tries and cuts to get the material off, so needless to say the cut isn't very clean.
Tomorrow we will be grinding and fixing the spacer and putting it all together. I will take photos of everything, including the old fork, new fork, spacer, adapter from Specialized, the headtube, and how it all goes together. I will also try to get weights of individual pieces and the final product, as well as the inner diameter, outer diameter, and height of the spacer and Specialized adapter.
I hope this helps someone. Suffice it to say this hasn't been an easy or stress-free project, but it will be worth it in the end.