I think I can shed some light on this as I went through the same thing when I first got my car and SB-100 numbers were out. Let me clarify that with SB-100, you don't need ANY smog devices. But without it, read on.....
1969 was the first year the 351 Windsor was manufactured. I have a 1969 351 Windsor in my car and I failed miserably the first time around at the BAR referee station (no, CHP does not smog, that's the BAR - Bureau of Automotive Repair - who determines smog emissions).
In order to pass, the referee told me I had to do the following changes as they were required back in 1969: Thermostatic air cleaning assembly with heat riser, complete the PCV system, replace my Holly 600 carb with another carb that has automatic choke (mine had a manual choke).
I bought an old thermostatic air cleaning assembly and modified it to fit under my hood. Installed the heat riser and strapped it to one of the headers. Replaced the carburator with another Holly 600 that had auto choke, and to complete the PCV system, I also had to replace my distributor with one that had a vacuum advance. Most of this was done by my mechanic who did lots of research. After all this, I passed! I had to go through this every two years, so I got an SB-100 number in 2005 and took everything off. Since I don't need this stuff anymore, it's up for sale:
http://www.replicacobra.com/sale/Parts.htm
The above does not guarantee that you'll pass. On top of all the above, you should not have a modified engine (stroked, modified cam, etc.) Furthermore, the above is for a 1969 engine; more items may be needed if your engine is 1970/1971 (potentially a smog pump as well). The referee will take a smog reading and you cannot be above the limits at the idle test and the 2,500 rpm test. Another forum member has a 1966/67 427 side oiler and can't pass due to his modified cam (cannot pass the idle emissions test).
The referee is extremely thorough and strict. He spent an hour going over everything under the hood. He even called Holly carbs and verified that my Holly 600 wasn't legal back in 1969. While there, he also looked through many books to verify my PCV diagram. He was a nice guy, but very strict. He gave the following diagram to follow:
http://www.Audioguy.net/engine.jpg
However, based on new information from Mr. Morgester (the deputy attorney general) who recently posted to Club Cobra, a newer 351 Windsor engine may potentially be substituted and pass 1969 requirements. This is new information to many, good luck with the BAR on explaining how an newer 351W engine that replciates the 1969 motor should qualify under 1969 rules!
If you have any questions, let me know. Good luck!
Howard