what size delete pipe?

[DEMO MAN]

i just purchased banks dual monster exhaust and banks designed it so that you cut the flanges off of your factory cat and install their pipes on to it. i dont wanna use a cat, i just want to put a piece of ss pipe where the cat belongs. does anyone know the length and diameter of the pipe i will need? i just wanna have everything in hand when im ready to install because i'll be doing this in a evening and part stores will be closed. thanks for any help. 2005 cc sb 6.0

[jagular7]

Measure the length of your cat pipe from the tightening flange to the slip clamp. The stock cat pipe uses a donut wedge front connection with a slip in end connection.

The issue is the front connection of the test pipe to the downpipe. The stock downpipe will have the wedge to fit the cat's donut and uses a pull clamp to keep them together. The cat test pipe (MBRP) uses a flat flange with a gasket. Can't use the stock downpipe with an aftermarket test pipe.