a first step extending above {HEAD ~ the top surface} of said housing and positioned adjacent to {TAIL ~ said passage} 
a first step extending above { HEAD ~ the top surface } of said housing and positioned adjacent to { TAIL ~ said passage }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL