Mike, do you just want to tow it a short distance or are you going to do a lot of towing behind a motorhome?
Crewzin has addresses the "short" tow. If you are going to tow for long distances, the answer is, it depends.
Towing four down is by far the most convenient (and what I do). It is more expensive due to the cost of the REMCO transmission lube pump and the tow bar brackets you will have to have installed (I use Roadmaster EZ brackets).
Using a tow dolly is the least expensive option (with the automatic) and avoids the need to make "modify" your PT. It is a bigger pain to hook up, you have to have a place to store the dolly (some RV parks don't have enough space at the site for a dolly) and you have to remember to stop after about 50 miles to check the tightness of the wheel straps.
Using a trailer (preferably enclosed) protects the PT the best but the trailer is heavy (the trailer and PT will exceed the 5,000 lb towing capacity of most gasoline power motorhomes and a few older diesel pushers), still harder to find a location for, takes even more time to load and unload than the dolly and is the most expensive of the options.
No free lunch.
Since you have the automatic, it will really depend on whether the added convenience when of towing four down makes up for the added expense and whether you can live with having the tow bar brackets showing. I will add that it does make transmission fluid changes more expensive since they have to remove the drivers side tow bar and reinstall it each time they drop the transmission pan.
Edit:
A few photos:

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2003 Almond GT AutoStick, body colored rear splash guards and hood struts, chrome gear shift, AC & vent knobs, billet steering wheel spokes and pedals, AMX1397 Turbo-Intake Pipe.