you may also be able to tap it and install a threaded plug. if you do this you will need to be very careful not to extend it much inside the casting or it will impede coolant flow.

this is probably a job i would take to my favorite machinist.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.