[Dangerous Doug]

Check the emissions regulations in your home state before you buy. In CA, anything after 1966 in the block date code means you have to put all the smog equipment on it---just as it was originally---and it has to pass the year block emissions requirements. Alternatively, you can register with SB100 but those 500 certificates go pretty fast. The 351W was not available in 1965.

One other question is what you are building. If you're building a 289 FIA then a 289 would be "correct". Lots of guys building the 427 S/C model use stroked 351's (427 seems to be the stroked displacement of choice). But beware: if you're building a high-end replica (ERA, Kirkham, Shelby) you should put in the "corrrect" engine (be it 289 or 427 SO) or your resale value will suffer.

DD