Ok a small update on my efforts for this... Finally purchased an Arduino board to play with and now have some code that I believe will read the output from the meter. Everything compiles and runs on the board, just have not had time with the weather to test it in the RV.
Plan is to use the Arduino to poll the TriMetric (and other items), right the data to a MySQL database on a Raspberry PI 3 that presents that data on a web page. I have the database and the basic web page working, now just need to get the connects between the devices working.
Walter