I took it apart and sectioned 7" out of the manifold. Rewelded the manifold back together, which was tough as it was galvanized and thin wall tube. At any rate, something else I discovered is that 2 burner 413's have the aux burner sitting just a bit higher than the main burner, maybe to help with gas flow. By the time I got the manifold aligned to weld, I discovered this. I'm thinking if I pull the restricter plate out of the aux burner, It will run hotter since it's the same size as the main on the newer 413's.
I decided that since the 2nd burner isn't as hot, closer is better and left it. It fired right up and the advantage is that you don't have to use a match to light the aux burner, just open a valve. This should really heat up a pan of water and get a high base waffle iron up to temp in a hurry. I'm thinking it will really be a real cooker under the oven as well.
Now gotta go finish the garage, or maybe play with the case....Doug