So I got the build sheet for my 69 chevelle last week and it says "SP350 V8 Engine 396", and I can't find what that option is anywhere, I have some info but not alot, I am so lost, any help would be appreciated  

try this...

350 horse power 396..    i think the 396 was normally a 325 HP motor...

try the 5th paragraph on this link... it sort of explains it..

http://www.carsofdreams.com/chevy_chevelle_396.html

most chevy history books will also have the info... along with how to books...  

The numbers matching motor isn't a 396 though, it's a 350, that's where I am lost at, the thing about this 350 is that it's bored and stroked and the bore is to a 396, and its all stock gm parts, it has no after market stuff.  I called both pervious owners and they confirm they didn't do it, and I have heard it existed and how many were sold to the public, but that's all I can find out.  If you guys have any info on that, or maybe know someone with one, help me out