Correct your are Marc, in fact the script isn’t even close when you consider the original sign typography, not to mention the text on the BACK of the sign :D
http://www.thewelcometolvsign.com/
PS: I am SO getting one of these :D
The Brush Script ID is valid, Bert — good job. 
I thought Las Vegas might be Ulissa Bold but — although the
earmarks match — the face is quite different and not even a
near match. Bugger …
Nevada could very well be Frutiger 95 Ultra Black, and apart
from the ‘C’ Welcome looks similar to plain ol’ Helvetica.
1959 — Designed by Betty Willis
Well just to be thematically appropriate, you could use House Industries {newurl\newurl{http://houseind.com/house.php?kit=VEGAS-FO&sub=view%2CLas,http://housein…} Vegas Fabulous} for Fabulous…
Yves, I don’t think Frutiger and/or Helvetica match… Considering the dating Frutiger is out of the question, of course. My guess is, one should look into transfer lettering of the time.
BTW: The stretching remark I made doesn’t make sense in this respect, either. Probably the “original” BrushScript is a bit wider than the one that’s digitally available — or the illustration has been stretched a bit.
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