Aftermarket Tach Instal?

[SRH916]

Hi, I have just bought a cheap little tach just for tuning, and to see what is going on, but I am having trouble finding where to hook up the green wire to the distributor. I have an HEI in my truck, but the whole engine bay is covered in cr*p so I can't really find the place where it hooks in.

Also I read on autozone.com which to me sounds contradictory "Never ground the TACH terminal; serious ignition module and coil damage will result." and just before that it says "Connect one tachometer lead to this terminal and the other lead to a ground." Does that just mean don't connect a wire straight from a terminal to a ground, or no ground at all?

Thanks in advance,
Jared

Oh, this is the tach that I bought. http://www.iequus.com/product_info.p...ory_id=100_120