How to install leviton 6230 timer switch

thanks. One last question. How do you connect the green wire from the timer to the actual box? I don't see any ground wires coming from the box.

just to clarify

I just checked the instructions and here they are:

Black leads to circuit's line conductor
Blue leads to circuit's load conductor
green leads to the circuit's grounding conductor
for 20A unit only: connect white lead to the circuit's neutral conductor.

Darren, do your instructions still apply? Thanks for all your help.

It's odd, but my house is new (2005). The one other time I replaced a receptacle with a GFCI switch there was a ground wire. I am not sure why it's not there, but thanks.

Update - Problem

I would like to thank EBFD6 and Darren for their help. I noticed two things when I began taking things apart.

1) The light switch I am replacing is only rated up to 15amps and my switch timer is 20amps. This is a problem, correct?

2) Before I stated that there were 2 wires going to the bottom screw of the current fan switch. It turns out it's actually one wire that has had a one inch portion stripped off in the middle and that was looped around the bottom screw.

Is it correct that I have to exchange the 20amp timer for a 15amp timer? Once that's done would I still be able to cut the looped wire where it's stripped and just pigtain it with black wire from the 15amp switch timer?

Thanks

Yes the breaker is 15a. Should I also be OK with cutting the one wire which has had an inch stripped off in the middle and pigtailing it?

The wires in my wall are solid, while the wires from the timer switch are stranded. Do I have to use a special marrette or can I just pigtail the different types?