You can either take Hwy 50 thru Lake Tahoe to Reno or go into Sacramento and take I-80 to Reno. Depending on your tastes, since you're retired I would take my time and enjoy the trip. Each stop below is about 2 1/2 hours driving time each day.
In Reno, we like the Grand Sierra Casino/Campground. Nice walking trails alongside the river.
Next up is Winnemucca, Nv. New Frontier RV Park is the only place to stay. Not much there so it's usually an overnighter.
Last town in Nevada is Wendover. There's a casino there that sits on the Nevada/Utah border. The casino is in Nevada, the campground is in Utah. Register inside the casino AFTER you put your rig in a vacant site. First come, first served. Using this campground as a base you can cruise over to the Bonneville Salt Flats.
Leaving Wendover, SLC is only 2 hours away. The KOA would be my first choice. They have a shuttle service that will take you to Temple Square daily. Ask when the Choir is performing and get some free tickets if they are. Use the toad to explore the Great Salt Lake. Or, if you're tired of SLC, head north to Willard State Park and explore the Lake from there. Lots of day trips available from there too.....Dennis