An update on my installation:
After the intial installation, my Sandia 165R transponder seemed to quit working! ATC was not getting a squawk - the ADS600-EXP seemed to be fine - I was getting GPS positioning to my iFly 740 along with weather and traffic. I sent the transponder in to Sandia and they said it was OK! However, while they had it, they did a revision/upgrade and then sent it back - all for free! Great customer service experience with Barry LeBlanc at Sandia.
I was suspicious of my transponder antenna cable as I had to manipulate it a lot since I mounted the ADS600-EXP below my transponder and had to remove/reinstall the transponder several times, each time flexing the antenna cable near the SMA connector. So, when I got the 165R back from Sandia, I reinstalled it along with a new transponder antenna cable. I clipped the TransMonSPE on the antenna cable about a foot from the transponder.
Everything is working perfectly now! ATC says the transponder is spot-on and the iFly is receiving GPS position, traffic and weather from the ADS600-EXP.
As far as configuration, I used the UAT Console program 5.3.1 and inputted my tail number and checked "Autostealth" mode, selected "TransMonSPE squawk and alt" for the input, and "EFIS" (which lists the iFly) for the display and left the baud rate at 115K.
Bill Moffett at NavWorx and Shane at Adventure Pilot also provided excellent support and I can't say enough how helpful they all were!
John