318 not a 360 help please!

Yep! I don't have a 360/727 drivetrain, I have a 318/904 drivetrain. I bought this drivetrain from a guy on craigslist in my area who told me otherwise and since I didn't know any better, I assumed he was right. Durrr! My ignorance got the better of me. On top of that, I had to clean up the engine just to see the casting number on the block to realize that I had a completely different motor! Oh well. You live and you learn right?? So back to my 318 deal....what can I expect to run into? I have already gotten with a local guy in my area who is selling me drag style headman headers, an oil pan, and valve covers, for this build.