Success!!!
Ordered a 4 button key from amazon.
Car Key Fob Fit for Ford 2011-2016 F-150/ F-250/ F-350/ Explorer 2011-2015/ Lincoln 2011-2014 Mark LT/2011-2016 Navigator 4-Button Key Replacement for Ford Key F-150
Got the 4 button key, programmed it to start the car with 2 original keys, (first key in, ignition to on for 5 seconds, removed, 2nd key in, ignition to on for 5 seconds, removed, third (new key) in, ignition on door locks cycled, removed, re-inserted, started car.
I then did the fob button programming by putting in new key turning from off to on (not start, but on), 8 times, door locks cycled, then pressed any button on key. Got out of car, checked that lock unlock worked, then locked door, pressed and hold auto start button for 2 seconds and horn honked and car started.
Finished by getting into car and putting key in and turning to on. Total success.
To enable remote start I used forscan and changed values in two modules as follows: (for my 2013 Explorer XLT)
BCM
726-19-01 0047 = remote start disabled
726-19-01 0148 = remote start enabled
IPC remote start options
720-01-03 C8F3 = without climate seats or wheel(Base model and Interceptor. Possibly some XLT models)
720-01-03 F823 = without heated steering wheel With climate controlled seats
720-01-03 FC27 = with heated steering wheel With climate controlled seats
Using information from the following posts:
Remote Start 2011-2015 FORSCAN
Remote Start Facts (2011 - 2015 only)
Hidden Remote Start?
Thank you to all who contributed to my adding a 3rd key and getting remote start working.
Roveer