I did not find any record of a marriage for Peter W RHEINGANS & Christina SAUERESSIG.
The only Peter I found was: Peter RHEINGANS, 18 Dec 1847 Germany - 13 Mar 1902 V3, P896Deaths, son of William and Margaret, married Paulina ______.
Are you sure they married in Ozaukee county? You may wish to check with surrounding counties (Washington, Sheboygan, Milwaukee, Waukesha) depending on where they lived. What church did they belong to? A marriage record MAY be found there.