I'm not a pro mechanic, but am mechanically inclined. Either way it sounds much worse than it was. Here's my version of the instructions.
Step 1: back car onto ramps (or not, your call)
Step 2: Support muffler with car jack. I used a hockey puck to be able to reach it without fully extending the jack, but you will need a full size floor jack for this or leave your car on the ground. I like the extra working room.
Step 3: Remove 4 x muffler hangars
Step 4: Slowly lower car jack to lower muffler. Do not let the muffler just dangle, you need to support it at all times or damage may happen up further up the line.
Step 5: Remove 1 x wire zip tie that's clipped into the frame on each side between the mounting points. This is necessary. The hitch fram must be flush against the car frame. Temporarily tape or tie the wire harnesses up and out of the way.
Step 6: Remove 2 x plastic pop-rivets (Pop center out with a flat scredriver, then pull the whole fastener straight out) from rear bumper under tray. Then use flat screwdriver to release 2 plastic clips and remove the trim. I honestly have no idea what the purpose of this trim is other than to cover up the bumper fasteners and brackets below.
Step 7: Remove 2 x more plastic pop rivets that are fastening the bottom of the bumper to the metal brackets that the last trim piece was covering up. Nothing else needs done here, just pulling those 2 fasteners give the bumper a little more flext to twist around the hitch as you push it up.
Step 8: Remove tape on the frame covering the forward-most holes and thread your bolts into the weldnuts in the frame. This makes sure the threads are clean and everything goes smooth when you bring the hitch over.
Step 9: Attach rearmost hardware to fishwire and pull fishwire out the rearmost side mounting hole, leaving the hardware in the frame.
Step 10: Tape "spacer washers" provided to inside face of hitch mounting plates. Make sure the holes line up. I used electrical tape. These spacers give just enough clearance so the frame weld and seam seal at the rear of the frame don't interfere with the hitch installation. Short of having these welded onto the frame this was a nice touch.
Step 11: Swing the hitch up and in, then wriggle the rear bar up and above the lower edge of the rear bumper so it's concealed. You're in the right spot with the edges of the towbar are above the bumper cutouts for the exhaust tips. Honestly this was the hardest part and I actually called the wife in for support to help support the hitch on one end and make sure I didn't twist it so it dropped on me or damaged anything else if I pushed it the wrong way. The extra leverage in the bumper just give a little play to push and pull at the bumper to get the hitch up and over it with the way I was supporting the muffler in place.
Step 12: Bolt in the forward most anchor points loosely.
Step 13: Thread the fishwire coming out of the car frame with the hardware attached to it in the frame through the rearmost hitch mount holes. Push the hitch up into place and pull the hardware through the holes in the frame and mount with the fishwire. Remove the fishwire from the bolts and put the nut on loosely.
Step 14: Put the push pins back in the bumper mounts before you forget
Step 15: Torque down the 2 hitch nuts and 2 hitch bolts
Step 16: Jack the exhaust back up to install height and re-install the hangars on one side, then the other.
Step 17: Slip a zip tie between the hitch frame and car frame approximately where the harnesses were tied down before and secure the wire harnesses back to the hitch frame.
Step 18: Crack a beer, and wish that the wire harness was currently available for yourself LMAO while wrenching on a brand new / perfectly clean car
I can attempt to get some post-install key photos the next time I'm outside in dirty clothes and can crawl on my back under the car if needed.
*****EDIT:
Yowza, all that came with my hitch was a single page of instructions with a diagram of the hitch and some words along the lines of what I wrote above. I REALLY wished I had checked the Curt website for instructions before I did it. They've updated the instructions on their site with a beautiful PDF file including photos, much like what I got with my MAzda 3 hitch. My guess is the hitch is so new it came off the line before the instructions were 100%. The manufacturing date on it was only 3 weeks ago.
Ahh well, I had fun conquering the new car. Link to Curt #12170 install instructions are below. The only thing I did extra then was pulling the 2 pins for the rear bumper and putting them back in when done.
https://assets.curtmfg.com/masterlibrary/12170/installsheet/CM_12170_INS.PDF