This was created from the XLForum posting by 4x4F150: https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-electrical/sportster-motorcycle-electrical-and-ignition/196469-wire-tuck-with-no-tank-lift-and-no-rewire?t=2073002

All the parts involved:
DK Horn Relocation Kit (needed if you have the “cow bell” horn)
DK V-Coil Relocation Kit
DK F6 Ignition Relocation Kit
Self Fusing Silicon Tape
Upgraded to HD tach/speedo combo gauge

I've seen other threads where people have done a wire tuck with no tank lift, but they all involve removing the plastic connectors and rewiring. I wanted to keep all the connectors and tuck the wires as best as possible (didn't really care if they showed a little). What I found is that you can completely hide the wires in the tank valley. This process also involves a coil and ignition relocation.

Here is what my bike looked like before I started.
I then removed the seats, tank, coil, ignition, and all the stock plastic covering everything to reveal this mess:
Next step was to move the ignition and it's wiring to the middle left side of the bike which cleaned up things a little.
I then wrapped all exposed wires in self fusing silicon tape. This stuff is awesome… didn't know it existed until I did this project. Never again will I use electrical tape for anything.
The key here is to not bundle all the wires together in a single wrap of the tape. Take each section of wire and wrap separately. This way you get more movement of each section and can position the large plastic connectors away from each other. I chose to zip tie the wires to the frame but I've seen others wrap tape around as well.
Here is a photo of the wires all up in the tank valley
And the final result of each side of the bike (I did use a couple more zip ties to get my trickle charger connection out of the way)

Since I have a 1200 custom, maybe this is only possible with the larger tank, but you cannot see any wires unless you get down on the floor and look up into the tank. I also swapped out the low gas sender on the fuel pump and installed the HD tach/speedo combo gauge, so you can see the new gauge in a couple of the photos. This new tach is great… 4 segment fuel gauge, tachometer, gear indicator, miles to empty, whole bunch of stuff… highly recommended if you want more info.

– Subsequent Comment –

There was no loom but there is 2 pieces of plastic on the right side and one piece on the left side that covers all the wires (didn't take a pic of that). The wires are all zip tied to the pieces of plastic and there's a bridge like plastic connection between the 2 sides. So the stock wiring is really secure.

You have to remove all this stuff to even attempt the wire tuck. Most of the plastic is hidden by the tank but you can see some of it in the first photo. (Best spot to see is between the tank and the oil bag… dull black plastic curving up and to the right and then under tank.)