Car Alarms: Subaru Legacy 2000 Tach Sensor, spark plug wires, subaru legacy

Question
I'm looking for my Tach Sensor wire. I know it is BLUE or RED/GREEN on my COIL.  However I'm unsure exactly where to tap into this wire.  On the top of my engine, I think the coil is the black square with the four spark plug wires coming from it. There is a wiring harness going into that, but I'm not sure that one of these wires it the wire I am looking for. Could you re-enfirce that I am looking in the right place?

Also, I'm somewhat hesitant about this wire because I'm not sure how to test it either. I've read that it produces an A/C voltage? Should I just change my voltmeter to A/C and what voltage should I read?

Thanks,
And here's the stats of my car:
Subaru Legacy GT 2000
4 cyl boxer engine
4 door.
pretty stock all the way around.  

Answer
According to my notes, The 2000 Subaru Legacy's
tach sensor wire, is yellow/green located at the
ignition coil. (can't be too many places under the
hood where you will find this wire.) Simply find it,
take the tach sensor wire from your remote starter
and attatch directly. It should show less than 1 watt,
but again, the remote starter is set up to read
the tach. It would see it a Negative so, it's a bit
confusing. Go ahead and find this wire close
to where you are already looking, and then do what
the remote starter manual says for tach learning.

You'll do fine.

ALARMTEK