Little late to the thread, but thought I'd chime in.
Every year in August there is a huge classic car show in Nevada. Hot August Nights. It's a car show that is all about classic cars and rock-n-roll. Personally, I only care for the Show-n-Shines. My grandpa used to take me every year in his 4-door 1959 Chevy Impala. I've seen some crazy cars from BMWs and Subarus, to your typical Chevys and Fords. You'll never see a vehicle newer than 1979, and you'll only hear music from the 50s, 60s, and 70s (sometimes live).
But there are other events. Parts swaps, drag races, auctions, live music, eating contests, etc. And every year there is a parade through downtown Reno that ends at the Reno Arch. You can find an events calendar online.
https://hotaugustnights.net/event-schedule/
Since your looking at historic tourism, they're holding a Show-n-Shine in Virginia City (a historic mining town) on August 2nd. I haven't been Virginia City for many years, but there is an old mine shaft you can tour in the back of the Ponderosa Saloon. It's a very fun city to explore; it's a city trapped in the 1860s and it has even been rated as one of the top 10 historic cities in America. It's only about an hour away from Reno, where most of the other events of HAN take place.
It's later than your planned trip, but something to think about. Just keep in mind that it can get hot in Reno. Especially in July/August. Not uncommon to see temps over 100*F. It gets even hotter if you wanted to venture to Las Vegas to see the Hoover Dam (I've seen over 110*F in recent years). But I would advise not bothering with Vegas at all. The dam isn't worth the trip. The only real "appeal" to Las Vegas is the casinos, and that ain't saying much.
Last thing to add. If you like America and classic cars, then go check out Vice Grip Garage on Youtube if you haven't already. That goes for anyone viewing this thread. Derek makes pure, wholesome, and family friendly content all about classic cars.