The best way to do either option is to tie/splice a 12" piece of 1/8" line to the end of your righting line. Use a sheet bend knot:

Option A (tie around the rudder pin) - there's usually a space under the top rudder casting pin lug where you can loop the small diameter line through and tie a bowline. It doesn't really interfere with steering, but because the line's in a "working area" - it will fray. You need to keep an eye on it and replace periodically.
Option B (hole in the deck lip) - the small hole can go pretty much anywhere, as long as it's not too close to the hull (leaks). When I used this system, the 1/8" line was through a slightly larger hole about 2" forward of the outboard transom corner. Just tie a figure eight knot under the desk to secure. No worries with wear as long as you smooth the edges of the hole.