They are a few ways to go about it since the headers are made for a slip fit connection... Here's what I was thinking.
I assume you have cats that you want to make removable. Ive done this in the past. Id make a slip fit connection to the header, and the cat, then another slip fit to the X/H pipe, then use the ball and socket connection to the cat back. Then what you can do is make a piece of pipe the same length as the cat and swap it out when ever you want for OFF ROAD USE
Since it seems he will be making or having a cat back made using the Borla ProXS mufflers, Id repurpose the socket parts your cutting off the Prochamber and use them back at the new cat back, weld them to the new "flowtubes" or intermediate pipes. This way you have ball and socket connections at the catback point which is easier to align/install.
If I make a full custom exhaust system I do all slip fit connections, but it has to be perfect or it is a bitch to align and put back on, this is mainly on race cars that do not have tail pipes.
I assume you have cats that you want to make removable. Ive done this in the past. Id make a slip fit connection to the header, and the cat, then another slip fit to the X/H pipe, then use the ball and socket connection to the cat back. Then what you can do is make a piece of pipe the same length as the cat and swap it out when ever you want for OFF ROAD USE
Since it seems he will be making or having a cat back made using the Borla ProXS mufflers, Id repurpose the socket parts your cutting off the Prochamber and use them back at the new cat back, weld them to the new "flowtubes" or intermediate pipes. This way you have ball and socket connections at the catback point which is easier to align/install.
If I make a full custom exhaust system I do all slip fit connections, but it has to be perfect or it is a bitch to align and put back on, this is mainly on race cars that do not have tail pipes.