That looks great abarrow. I'd like to copy it. Where/how do you get your NMEA stream into MQTT - is it a signalk plugin, do you construct it in signalk and send to mqtt_out, localhost:10110 doesnt work anymore,.... I'm stumped! Can you share how you did it? 
You mentioned a suitable casing. The 4x20 lcd is typically used for the 3d printer display, so there's a bunch of stl files out there - maybe like this https://www.thingiverse.com/thing:1903059. Our library will 3d print your stl file or there are internet based 3d printing services like Shapeways. If that does work out - I could print and mail ya one.
Thx!
You mentioned a suitable casing. The 4x20 lcd is typically used for the 3d printer display, so there's a bunch of stl files out there - maybe like this https://www.thingiverse.com/thing:1903059. Our library will 3d print your stl file or there are internet based 3d printing services like Shapeways. If that does work out - I could print and mail ya one.
Thx!