Exhaust Muffler question

[super dave]

I am starting to work on my Exhaust system but in doing the search here there are some questions unanswered. What is the length of the Original muffler body as I know it has an 1 1/2" inlet and outlet and is 6" in diameter, My best guess is 17" ?? Also the pipe going from the Exhaust manifold down to the cast elbow looks to reduce down a size going into the elbow, Did it have some kind of asbestos seal that wrapped around the pipe going into the elbow ?? (see picture) as the parts book also seems to show the pipe #CTL 109,110 SA in illustration No 24 having a reduced section just going into the cast elbow.