Propane pressure regulators

[Arby]

So I have a propane question. I bought a new RVQ portable BBQ. It comes with a small propane regulator and uses a small propane bottle. I want to connect it to the propane line on my trailer and hang the BBQ on the side of the trailer.. I'm thinking all I have to do is put a "T" on the propane line downstream of the regulator at the trailer and remove the small regulator on the BBQ (since the line propane pressure is already regulated). Is this correct or am I missing something ? Would it hurt anything if I left the small regulator on the BBQ and just had 2 regulators on the system ? Any advice is much appreciated.