Step 5: Drilling and Final Steps...
Only other alternative is to remove a tone or volume (volume if you are crazy) pot if you do not wish to drill your guitar. However the switch might not fit perfectly so you may have to do some filing etc to make the switch fit.
Test the switch before you place the cavity plate back on. (I highly recommend screwing your output jack back on before you test the switch, Because you are going to be pluging you're amp in)
If it works, and if your switch is mounted on your guitar then congratulations, This is my first guide so I may have forgotten somethings in the step by step, If you notice any thing or have any questions, comment me.