I hope you post your follow-up soon. I have an 820T dongle, and have just ordered a new IC-7600, and was planning to do exactly what you have done. I am so glad I found your post.
You used the Mini-Circuits ZFSC-2-1 divider. I will use it, too.
I have over 200 of these dividers in stock, new, and sell them on e-bay under my call sign W8ASA.
If you need one, just let me know.
I also have lots of different SMA connectors in stock at www.ohiomicrowave.com
. Mention that you saw this on eHam and I'll give you a special price you can't get anywhere else.