CB350 Handlebar switch question HORN GROUND?

[MB]

So, I am installing this switch
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=360375677203&viewitem=&sspagename=STRK%3AMEWNX%3AIT#ht_500wt_956
It's a hi/lo switch with a horn. I know where the three switch wires go, they correspond with the shitty switch I have on now.
The question is the horn. Do I have to run a ground from the SWITCH for the horn to work or can I simply hook it to the button, and run a ground straight from the HORN to the frame? The horn is being ground in it's current configuration already (running a kinda "straight line from back to front with no signal and it adjoins the ground for the rest of this electrical)... Anyway, not to confuse things
Ground from switch necessary?

 

[hond cb350e]

yes it needs to be grounded for it to work

 

[Kong]

Find your original wiring diagram and look very closely at how it is wired. Horns are often different than other electrical devices on a bike or car. The difference is this, with most electrical end uses, things like turn signals and lights and coils, the device is grounded and the switch that controls it sends power to it when you close the switch - so the switch is the source of power. Horns are often backwards - that is to say they receive power constantly and what the switch does is complete the ground circuit - the switch is the source of the ground, not the source of power.

 

[MB]

Yep, makes sense now.
Someone told me that for the ground wire from the switch I need to use a thick wire like the household stuff. Is this true? I picked up some 20 gauge from Radio Shack, was hoping that was enough