I just wanted to thank everyone for their great advice! We have safely arrived in Seattle and our cats are adjusting to being away from home. We ended up driving for 2.5 days as we had a tire blowout on day two that ate up so much time we ran out of energy in Salem, OR and had to stop for the night. The cats did well in the hotels, coming out from under the bed and exploring after only a couple hours. We had no trouble catching them and putting them into the carriers the next morning.
Our only problem was that my male cat peed in the cat carrier early in the day each of the days we were on the road (day one it happened less than a mile from our house!). I think he was just afraid and that made him empty his bladder. We had plenty of towels on hand and just swapped out the towels as needed, wiping down the inside of the carrier at the same time.
We also discovered that Mr. Bruno absolutely LOVES honeysuckle! A local petshop in Phoenix sold it to us as a possible method of calming him during the car ride. We showed it to him at home and he went crazy for it, trying to rip into the bag and indulge. It helped some during the ride, just sprinkling it on the towel inside the carrier.
Again, thanks! Now we just have to find a place to live...
Cassandra