Early A headers ( small block )

I'm still pretty new around here and figuring things out. It seems like there's quite a bit of discussion about fitment issues with headers. Do you know what sort of issues would I run into with these on a '65 with a 273?

I have Spitfires on my car, and other than not being able to use them with a 4 speed, and maybe not with power steering! My car is manual steering and automatic, and they fit with no problems! You have to clock the oil filter adapter to play with the headers, that's about it!!