I run those on my duster, you can change all 8 plugs in about 5 mins, i install mine from under neath by removing this center link from the steeing box and idler arm, and both outer tie rod end, this opens up underside and the headers bolt right in. Both #1 and #2 cylinder pipes are slip fits and install from the top. Its the easiet set of headers i every had, I also run a 727 trans, a moroso pan. The headers make very good power also.