I just purchase wall sconce to mount in my hallway. There is no existing fixture and I'll be powering it from the hallway light so they'll both work on the same switch. The new light warns me that older houses use 60 degree wiring and this light requires 90 degree wiring. The wiring from the new light to the old one will be rated for 90 degree the rest will not. The unqualified gentleman at HD tells me this is ok. Is it? I don't want to burn my house down or violate any codes.