I have used TTS on an 06 Dyna.
I fitted O2 sensors. They are not overly expensive.
As stated, the wiring is already present, as are the bung holes in the stock headers.
It was a 103, so the 88 issue did not arise.

I am currently using a 103 map in my 96, which works really well.
Just loaded the canned map, and no issues.
I tried a number of 96 maps, and they all ran poorly. Hot, and pinging.
So rather than get involved in a big tune up session, I decided to try the "bigger" map.
Temperature, response, idle, power, economy, no probs.