I have read here that drilling small holes in each of the units helps to get rid of the condensation. I have not done it myself yet.
Mine has little holes drilled for that reason many years ago, with no effect, beside the amp dial now never goes to zero! Only the fuel meter stays clear, all the others become cloudy. I am trained to park the Morgan with the meters turned to the sun (If there is sun), then they stay clear most of the day. It isn't just on humid day, it is: always! Indeed, I think: they always do that, sir!!
You can live with it.......