How long approximately should it take for the temp guage to come to normal? I know it depends on the ambient temp somewhat but I am up in the snow line at 6000ft and it takes about 10-12 miles! Is the stat stuck open?

98 Disco 1

 

Living in Colorado, that is what I see with my D2, yours is pretty normal.
You are not starting it up and letting it idle to warm up, are you, if so stop that practice today. Start the engine, let it idle for no more then 1 minute or all you are doing besides waisting gas is polluting your engine oil.