I will soon be ready to put some exhaust on the 57 GMC 370 LCF with a 270 6 cyl. engine. I have 2 questions.
It still has the original muffler hanger. Looks like a big "J" -- and would accommodate about a 6 inch diameter round muffler, maybe larger.
1st. Any suggestions as to what kind and where to get the muffler?
2nd. What diameter should the exhaust pipe be that connects to the manifold? (I plan on getting a shop to make one)

Note: Presently it just has an exhaust pipe and no muffler. Also the pipe was on it when I got it. It is not correct and seems too small, because it just wobbles around where it is bolted to the manifold.
The manifold is the 3 bolt flange.

57 GMC LCF 370
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