As Bob Smith says, there is no "conversion" to diesel because it is an entirely different engine. You remove the LP genset and replace with a diesel genset which you bought at full retail price (not the $3500 difference). This also means you add the plumbing to draw fuel from the coach diesel fuel tank, no small chore in itself. Hopefully someone buys the LP genset from you some day and you recover some of your cost. Or maybe the dealer takes in it trade on the diesel genset.
In short, it's not a practical idea.
Conversion from LP to gasoline is a more practical matter, since the genset is the same and you merely need to replace the fuel system components. Still have to deal with plumbing to the gasoline tank, though.
I agree with you re the LP genset, though. An LP genset is going to be a pain if you need to use it for extended periods in cold weather - they suck a lot of propane.But is the fuel tank on the View big enough to support extensive use of the generator too? It's only a 25 gallon tank, so if you arrive with less than a full tank of diesel, you are going to run short there too.