Are you referring to the electrical switch portion or the mechanical
lock (where you insert the key)?
Assuming it is the electrical part that you want to replace:
a) remove the lower left dashboard cover
b) if possible extend the steering column backwards and lower
c) remove the lower steering cover/lower trim panel which covers the ignition switch area (held by 1 plastic screw)
d) detach the various connectors that blocks the way to the switch, or at least cut the tie straps bunching the wires together)
e)remove the 2 tiny screws (with no heads) which are covered/hidden by wax or epoxy that holds the switch
f) remove switch and replace
