Does the dash have to be in to install windshield

Yes, they are. The windshield gasket covers up the bolt holes and you can't get the dash in with the windshield in. If it's a freshly painted hull, it won't hurt it to get wet. You can dry it out when you get it home. If you really need the windshield in, they could put it in and you can get a glass guy to take it back out when you get it home so you can put the dash in.