When Ulysses was still a companion in the game, he was indeed meant to be recruitable at the location that became Wolfhorn Ranch, as some people have guessed from the fact that the location was called "Ulysess' camp" in some localized versions of the game. This version of Ulysses would actually not be open about his allegiance with the Legion, but rather try to gently steer the character to more pro-Legion views while offering commentary of the various locations and events of the game. Ulysses would only openly admit his pro-Legion beliefs when dealing with a Legion-affiliated PC.
The Black Mountain location was meant to play a larger role in the NCR/Legion conflict at one point, with factions interested in controlling it due to its satellite system (the NCR to expand their broadcast range and the Legion to use as a jamming system). Digging through the files of the game one can still find some references to a quest that involved blowing up the satellite dishes that was tied to that older design of the area.
