Tire Pressure (Trailer stamp vs tire info)

[gonzo628]

So, my 3124 has Carlisle Radial Trail tires (225 75/R15 LRE) on it. Their max pressure is 80psi. The trailer stamp says the trailer was spec'ed with 225 75/R15 LRD (max pressure is 65psi. My question is... Which do I adhere to?

How do I tell what the rim was spec'ed for? (Another member mentioned the rim -in his situation - being insufficient for the tire rating).