Learn the difference between aftermarket headers and exhaust manifolds by watching this Summit Racing Quick Flicks video. There are performance advantages to both aftermarket exhaust headers as well as exhaust manifolds.
You can find out what they are by clicking that play button.
How much is just Stock one for 1993 Ford F-250 5.8 engine size
I expect the Header is sized for the engine it will be used on- 305, 350, etc.. Are there any tables or cross reference sources that helps w/ the Header selection to easily fit in a manufacturers particular body / model ? Example Stock ’79 Chev. Nova 4 dr., 305 V-8 w/ auto trans.