quick stack question for u guys, when u installed the flex pipe does it connect to the y pip from the bed or does it connect to the piping regular exhuast under the truck cause the sent me a 4 inch 90 as well as 4 inch flex pipe

 

I used the box tubing method instead of the y pipe. I had to install a 90 on the bottom side because I couldn't flex the flex pipe enough to make the corner. It also would rub on the frame cross member if I didn't use the 90.

 

Here is how I did mine.