the k5 is my buddies, big block mud slinger,always in the shop, lol. the headers are hedman #45006 mids.i have had everything in the car to check fitment. everything is good( I have hooker clamshell ls adaptors). did smack my air box with coil bracket by not paying attention. I have had this engine in and out bout 5 times now. yup , the EFI/LS is pretty much the route we will be going from here forward. next is my buddies 70 chevelle. !