Question about Guncon2 on PC

[The cranky hermit]

I am assuming 2 things about using a Guncon2 on a PC:

1: It works best on a standard definition TV
2: You need to plug the Guncon2 into a composite video port.

I would like to use the Guncon2 on a TV connected to my PC through S-Video. I looked at this guide here:
http://intruderalert.myarcade.org/GUNCON2.htm#SVIDEO

Both solutions involve hacking an S-Video cable. My question is, what if you use a TV that has a composite-out port on the front? Couldn't you just plug the Guncon2 into that? If not, could this device be used?
http://www.pcclub.com/product_detail.cfm?itemno=A9654004