I drive my open hooded 406cu in blown 1931 ford coupe from east of the Sacramento, CA area to Pleasanton, CA every year for the GG West Coast Nationals, Spring Get-Together and on occasion the Fall Get-Together about 150 miles each way. I have been passed by dozens of CHP officers over the years, as well as local police and never had a problem. As long as your not screwing around you will be fine.
If you get to Cali, make sure you get over to Highway 1 at San Francisco to at least Big Sir, that stretch is 150 miles long. You can actually take it from San Francisco to L.A. One of the most beautiful picturesque roads in the country. Make sure you have a lot of time and, it's a curvy road, but breathtaking!
As far as smog goes, pre '74 vehicles are exempt. Yes, the law states that if the engine in a pre '74 vehicle is replaced with a newer engine the car has to adhere to the newer engine smog test standards. I have never heard of this happening but it is the law. I would never voluntarily take my modified car to a the smog referee (different from a smog station or gas stations that does smog tests) to be smogged because I put a newer engine in it, that is just suicide here in this state. Also, when you move to California, you have 10 days to register your cars and get a California drivers license.