ORIGINAL: jrcaster
The magnum .46 comes were you can change it from rear mounted needle to carb mounted needle. You can't do that with OS?
The needle on the 46AX is mounted to a support which is screwed in with the back plate. You can rotate the needle 90 degrees on the bracket, or you could mount the needle somewhere else if you wanted to, but it would remain a separate entity from the carb, attached only by a piece of fuel tubing.