UPDATE -
I went ahead an purchased the upgrade kit from Dyers RV online. (we got the 5th wheel for one dollar, and we are going to keep it, so it was worth it)
Just got Back from Montana, and it was in the mail. So I put it in today. I had EE error code on the thermo, once I reconnected electrical. I did a 5 button CCC reset and it worked. However, only one mode showed, so I had to turn the furnace DIP switch to ON and performed another reset.
We are working again! thanks for all your suggestions. and assistance!!