stinger 3" to 2x2.5" install questions

OK All, I'm a bit late to the stinger exhaust install party and have a couple questions.
this is regarding the 3" down pipe to 2 x 2.5" setup.

Is the kit that well cut and bent as to almost be plug and play after removing the oem setup?
What if any trimming is necessary and can you use the existing muffler hangers?
Did anyone take their kit to a muffler shop and have it "hung" ?
I've tried to loose fit the pieces and am struggling to see how the pipe after the muffler will connect and still allow the tail to connect correctly.

What I'm seeing after a couple hours on my back is that the y pipe needs 6" or more cut.....but I walked away first to fight another day.

Did anyone modify the old cat hanger and weld it to the system to add support?

I welcome the feedback.

I installed the same set up last year at a local mechanic shop that had a welder, I use 2 hooker maxflows and a short 6" race bullet in the down pipe to quiet it a little more. I do remember them trimming some off of either the Y pipe or the down pipe to get it to fit with the mufflers in the stock location, no biggie. The most cutting and welding had to be with the tailpipes, as shipped, they just didn't fit right, had to cut some here, cut some there, weld back together and such, but it still only took maybe 2-3 hours to do complete. I held the tailpipes where I wanted them to sit, and the shop owner marked and cut and welded to complete it. I used the factory hangars in the back for the tailpipes, as well as the muffler hangers welded to the mufflers. It came out great with no low hanging sections or loose parts.

I put the whole 3" Stinger system on last year. He leaves each section long. I did go to a muffler shop to tweak it after installing especially around the rear upper control arms. I still have some rubbing on the rear brake cable cross bar.