On my HLM507W, it is very easy. The lamp comes in an assembly. Unscrew one screw on a back cover on the left side of the set, take the cover off, loosen two screws on the lamp assembly, slide the assembly out, slide the new lamp assembly in, tighten the two screws on the assembly, replace the cover, and put the screw back. It took 2 or 3 minutes. It is definitely user replaceable. I would assume the HLN models are the same.