Bought these outlet manifolds for my 79 f250 351mm. I chose the wing well because my truck has 4 gears. Fits as expected. When I bought them I knew I would need to route the brake lines that run from the master cylinder to the driver's side frame and cut the bracket that holds them. After two starts and driving the truck, Twisted immediately checked to make sure the bolts were tightened again. work fine, currently no leaks or problems with 4k. Would buy them again with great pleasure.