help! which model ps2 have I got?

[dosedose]

Currently installing chip, but confused. Thought I had a v4, my machine is a 30003 (no R), 8 screws, Hazard warning, serial number starts with B1.... but using the pic showing how to fix the rgb/dvd green screen problem (see http://www.dvdfix.dk/images/diagram/ps2v4rgb.htm )
I don't seem to have the small connection point. How come?
I've heard that there are some 30003 models out there that are actually v5s. Is this true? How can I tell?

Thanks in advance,

dose