Re: notching TH 350 pan?
It shouldn't be any problem to do as you have said. I am running the same drivetrain/same vehicle as you. I re-formed the stock stamped-steel pan to do the same thing. Cast aluminum parts are usually (if usa) 356 aluminum, and can be welded. You will need someone with heli-arc (tig) capability, and aluminum experience. I would suggest finding the welder first, and talk to him about what you want to do. He will probably suggest you go ahead and remove the pan, and get it REALLY clean. Oil in the pores of the metal will drive him nuts when trying to weld. He might suggest cleaning it real good with solvent (maybe even acetone and alcohol), and pre-baking it in the wifes oven. 400 degrees for an hour or so, would out-gas a bunch of stuff that would drive the welder nuts. For the new material, to weld in and form the new shape, he might suggest 6061, maybe 3/16, or 1/4-inch thick. With aluminum, it is usually advisable to 'v' the weld joint, so the welder has room for a substantial bead. Use a die-grinder to 'v' all of the weld joints.