It is a matter of common knowledge that finding a hideout just by knowing one part of the coordinates is an easy task for one or the other cacher.
Well folks, this one should then be an easy task and done within minutes …
The header coordinates show correct longitude.
Have fun!
18052008 V1.1 Hint 3 adapted
P.S.: Since this cache is half traditional and half mystery the 2 mile rule (3km) was multiplied by 5 in accordance with the guidelines (good reason) 
P.P.S.: You won't find any great views at the final location. If you'd like to enjoy a great view over Vienna we recommend to visit the place marked by the header-coordinates!
You can check your answers for this puzzle on Geochecker.com.