I used to use Techron to clean my fuel injectors, but failed to find any difference in performance. Techron is made by Chevron. Both Volvo and Mercedes-Benz have issued factory service bulletins advising the use of concentrated Chevron Techron in repair procedures for vehicles with certain mechanical problems.
Do not use Kerosene or any magic wonder oil etc... . I did with my old 1966 mustang 289. It made a real mess.

Most gas has additives which will keep injectors clean. These same additives can cause buildup of carbon on the backs of the intake valves.

Try using a bottle of AMSOIL PI (bottle does 20 gal, costs about $10) or BG-44K (can does 20 gal, costs about $25-30). I think you might feel some improvement.
If so, use again at recommended intervals. If not, you aren't out much (and the intake system will be cleaner)

If you ever tried to burn kerosene in a Coleman (naphtha or white gasoline) camping stove you would conclude you shouldn't put it in a car's fuel system. It's pretty good for cleaning bicycle parts though.

No. There are no cleaners in kerosene you buy at the store. I would be afraid that deposits would stick to the inner parts of the injectors as the engine cools down.
So long as you buy good quality gasoline, the injectors should be good for 150K+ miles before a professional cleaning is needed. That requires sending them to a shop. And at $15 each, it is cheaper than buying the bottled stuff and using it twice a year, which does not do much.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)