I use the 1 1/4" o-rings and hook them over the heated grip wire. I used this on my last bike for years and on the Connie since I bought it in February. Works great after you get use to twisting your wrist the other way on decel. You can pick them up for penny's at a hardware store.
I rode with a guy that put them on the other side as you suggest, and he told me he loses them every now and then when he rolls it out of the groove. $6 isn't much but a trip to the local CAT dealer is a slight pain for those that don't live in farm country. Jay rode my bike one day and was not used to it so I told him to cut it off without even thinking twice. As you can see I carry extras.