Didn't know they made a 488 fan in the wedge chassis . Thought they were only in the old pre 94 body then in the evolved 94 and on? I presume you already know it but if you change the manifold length or expansion chamber length/shape it will negatively affect exaust gas scavenging and give less power and usually detonate pistons . Good luck with your project , was a lot of those around back then ,were a pretty good machine .My DG pipe came in this week. To my surprise it's not made for an Evolved chassis. This pipe was made for a Wedge chassis. I will have to modify exhaust manifold flange angle a bit and cut an inch off the tail pipe end and use stock mounting hardware to make her fit. Jetting/Clutching are the same though.