Peter and Christian Hollebusch (aka Hulpusch, Hollowbush, Hilbish) -- 1749 Immig
There is a website that is very thorough and especially well researched and documented that anyone researching any person with the above mentioned surnames should know about.
It is the site of Alicia Hilbish Blackman:
Alicia dispels the many myths surrounding the origins of this family in America as told in many places.She traces the evolution of the surname from the Hulpusch spelling of Wiedt, Germany to the Hollebusch (and variations) of Montgomery County, PA to the modern Hilbish spelling that was adopted about the time the family moved to Northumberland/Snyder County in 1802.
In making her case, she cites many documents that she has uncovered relating to this family whose very existence seems to have largely gone previously unnoticed.