I believe for a smaller panel - maybe 50 watts or less - you don?t need a regulator. It won?t put out enough current to damage your battery.
One thing to consider: if your TT is ?solar ready? the plug on the roof may not be fully wired to the battery. On mine, it just led to a cabinet space where the regulator was intended to be installed. If you have an intelligent charger in your Puma, it might be easier and cheaper to just run an extension cord to the TT and let the converter/charger keep the batteries topped up. If you don?t, a battery maintainer is pretty inexpensive.
I?m not trying to talk you out of solar - I love mine. I?m just thinking if its main use is to keep your battery topped up at home, there are easier, cheaper ways to do that.