I used these headers on my 400 4 speed swap and I was supprised we only has to put two very small dents in them Barely 1/4". Passenger side by upper a arm and drivers side by steering shaft. Not bad for $130.00. Just a temp part till I could afford my ceramic coated kooks. I assume the fit will be better in a 68-72. Pics of them on page two of my build https://classicoldsmobile.com/forums...-400-swap.html

 

thanks for the review!
i'm looking to do the same to my 67 442!

 

good luck with it. for the money its a no brainer.