Sooo what happened was that we drove by here hoping to get a couple of pictures with the sign before we left Vegas. We ran into a couple of problems: there was not a lot of parking and there was a looong line to take pictures. We even saw people in wedding dresses (yes plural) come to take pictures so you know it's serious.
As for parking, you either have to just get lucky and find a spot, park illegally in makeshift spots, or park further away and walk.
As for the long lines, this was because people wanted to take pictures right in front of the sign. That gives people the best shots but they usually take a while to get the "perfect" shot. If you want just the sign itself at an angle, you can probably skip the line and just take the pictures and leave. If you have a selfie stick that might be easier to take a picture and wouldn't need to wait in line.
Of course, this all depends on what time you go. We went at around noon so we actually shouldn't be surprised at how many people there were. If you want to avoid the large amounts of people, I recommend going super early in the morning.
This was a last minute decision for us so we didn't get to take pictures and thought the long line wasn't worth, but if we're able to squeeze this detour into our plans the next time we come, we will make the stop here.