RE: die size for 2-56 rod
You don't need to heat it to a cherry red. Doing so gets the steel up to critical temp which, as Gray Beard mentioned, can actually give you a brittle piece because the air can serve as a quench. If you'll use a regular lighter to heat it to a gray temper (that's one color past blue or about 900 degrees) it will be fairly soft with no chance of being rehardened as it cools.
So to the OP: is there a reason you don't want to use the pre made 2-56 push rods from the hobby shop?