depends on what the 318 is in most likly
the ones that hang down under the steering is an A-body header
B-body,c-body,trucks are diffrent but some brands will interchange bodys with a 318
get the headers with the ball end collectors and loose the gaskets at the collecter flange
got new headmans for my truck fit good and has no gasket on the collector
thats the ones that have allways givin me trouble with any headers for a 318
I allways remove the studs on the ends on a teen and use sealer and a header bolt instead
it makes install a little easy-er on an A-body for sure
OH! FYI.. and if its a smoger,make sure you plug the air injection hole under the exhast ports...the header flange will not cover them