Here is my pleasant experience this weekend. First off I sprayed some penetrating lube on the manifold to midpipe bolts. I got lucky and didn't even break one of those square thingies. And those factory bolts are long. An air wrench would have been much faster. If you use an air wrench I would start with a rachet to get it started and have the retainer bolt against the stops before going to the air wrench. If you decide to not cut them off.
Another tip is to slide the muffler section as far as it will go. That will help with connecting them as one. You might even have to unbolt the mids to line up with the muffler. I tried that and it still did not help with my mids. Plus as you can tell there is not much room to play with up there.
Unplug your sims before trying to take them out. I couldn't reach the front passenger side to unplug. So when I installed them again I gave the sims a good 8-10 turns counterclockwise so when I screwed them back in the wires would not be in a bind.
My overall install, which is not finished yet, has become a pain in the but for me. I can't get the mids to fit on the muffler section. It seems the mids need to be a little smaller on the OD for the slip joint. I can not get the extension (QC only) piece to fit on the mids. I even tried sliping them back over the factory cats and had no problem getting them started.
I put the extention piece back on the muffler and seems like the mids are just a hair too long to go together. And I couldn't figure out how to slide the mids up further and still be able to line up the extension. But it looks like it might just barely fit if I can get the extension to go over the slip joint as far as it will go, then I might be able to slide it back on the muffler. But right now it will be in the hands of the exhaust shop for me. I had enough after a day and a half of trying to get it together.
Oh disconect your battery before you start on the driver side. Starter is right there.
Overall I would suggest sliping the mids on before you bolt them up if possible then install the sims(don't worry about plugging them into the wrong plug, it won't fit. I also found that out too.

) Get some lock washers as suggested above. For me on the bolts I had the nut facing down for tightening purposes. I had heard somewhere you should always tighten on the nut and not on the bolt head.