Hi Whitey,
You're not too far from Joshua Tree when in Havasu. A little more than the hour you mentioned, but well worth it. Could be a really great day trip. Depending upon how far you want to drive, there are a couple good circle type drives you could do into California. North to 40, west to Needles and up or down 95 for a way. It's a great stretch of Highway in either direction. North you could go just shy of Las Vegas, cut over to 93 and go back through Kingman. South you can go all the way to 10 and east to Quartzite and up through Parker. You can also go west further on 40 and hit the Mojave reserve and go south to old Route 66 and hit Amboy. There's a great old Route 66 gas station there, but I can't remember the name now. Really cool sign if you're into that kind of thing.
Hell... it's all good. You're going to have a great time.
Bill