Well here's the verdict. I now have cruise control on my bike! I took my bike in at 10K for preventive maintenance and found I needed my DPS replaced (SO glad I have an extended service policy!). While the bike was in service waiting on parts I had service order a right hand control cluster for a 2015 RSS SE5 which has cruise control. It works perfectly, there's even an indicator icon on the instrument cluster that shows the cruise control is on and the switch itself lights up. Works like a standard cruise control, even the resume cruise speed option. So, I have not talked to the mechanic yet, just the service advisor, however he said there were no problems. Will dig deeper later but now for the fine print...
I can not guarantee this will work for your machine, but MY 2015 RS SE5, that did not have cruise, now has fully functioning cruise control, just by replacing the original RH cluster with a RH cluster for a 2015 RSS SE5.
I'm sure there are you guys out there who do your own mechanical work that could have done this a lot cheaper, but that's not my gift. I read of some people who took a 3D printer and fabricated a switch, installed it, connected some wires, and eventually made it work, but that's not me. Just wanted to post my experience so as I did, someone else can find some info to help them decide their course of action for their Spyder. Now that I have a machine that I know I'm gonna keep, (I REALLY needed cruise control)...It's Time To Farkle!!!