PRNDL switch on Autotrans

Could someone tell me how to install the PRNDL/neutral safty switch on a 93 automatic 240?

Most cases they only need adjustment, I have never seen them go bad

see the old one broke off so I drilled it out untill I thought i hit metal. Now I need to know If it should be completly hollowed out? How does the nipple part of the switch work?(the part that goes in the tranny)