The car manifold has a rear outlet and the truck manifold has a front outlet. I did mine by using the car manifold as a base. I marked the car manifold with the approximate location of the outlet on the truck manifold and I drilled it with a hole saw slightly smaller than the outlet inside diameter. I used a hacksaw to cut the outlet off of the truck manifold as far into the manifold as possible to provide a nice flange for welding, parallel to the manifold surface. The truck outlet was then welded to the drilled car manifold in the same position as it had been on the truck manifold. A buddy welded it with an AC welder using nickel rod, no preheat. I removed the heat riser baffle and welded a divider plate in the same location. The plate should not fit snugly as there should be a minimal amount of exhaust transfer between the front and back cylinders (the oldtimers say 80-85% blockage is about right. I did mine in a '51 car for 10 years and it has worked fine. This method is much easier than sawing the two manifolds in two and joining the respective car/truck outlet halves. If I had ground the weld, it would look like a factory casting. I'm sorry but I did not take any photos.
