BLUF: Where should the Legendary FSX files be in relation to Captain Sim folder.

I have FSX SE. I installed both the Captain sim 707 base file and the legendary 707 in the main FSX folder (per the instructions) when I'm accustomed to loading addon aircraft in the Sim Objects/Airplanes folder. The Captain Sim base 707 variants work, but I can't get the legendary 707 variants to load in FSX. I moved the legendary 707 files to the SimObjects/ Airplanes so they'll show when I start FSX. The Legendary 707 planes show, but with a question mark and no pictures. When I try to load them it seems to freeze or close my FSX.