1968 GMC C2500; how to get rid of water spots

[gmc396]

I believe my '68 has the original paint from the doors back. The hood and front fenders have been sprayed at some point, and it looks like enamel. The truck is my everyday decent weather ride, and it goes in the garage for the winter. I wax it every winter.

The water spots after washing seem to be getting worse. I wash it in the shade and avoid hot days (we don't have many up here). I dry it off before the water evaporates. We have well water that is softened. This is the 3rd time I washed it and you can see the water spots in the pic.The enamel paint is fine; shows no spots.

I used a cleaner and then wax over it, and it looked great after I was done. But by the end of the summer and a few washes it is full of spots.

Should I try a ceramic coating? Or any other suggestions would be appreciated.

Thanks,

Ken