I found this Youtube video that was just posted Dec 31, 2018. The person is showing the underside and guts of a 2005 Super. I suppose this is the Series D or at least very similar.
Anyhow, it does a good job showing how the secondary air linkage works. Also good detail for inside the firebox. (Warning: If you cringe at seeing rust, this video may not be for you.)
Here is part 2.
Anyhow, it does a good job showing how the secondary air linkage works. Also good detail for inside the firebox. (Warning: If you cringe at seeing rust, this video may not be for you.)
Here is part 2.