it may seem puzzling at first..... but i managed it on the first time i ever got underneath the car

without the guide of the old cable to go with either, as it had broken and some had fallen away. the haynes manual is actually partially helpful for this job!
look down under the distributor cap, find the cable latched onto a swinging arm (far too stiff to move by hand), then follow where it goes back, under, and across to the driver's side pedal box. should be a lot simpler with that as a guide.
However, I won't lie to you - unless you're an anorexic russian midget gymnast, it's a pig of a job reaching into the pedal box on the car interior side to fit that bit of the cable. Very cramped, i nearly choked myself on the wheel as the only way my chunky frame would fit is to push the chair right back, recline it, then lie on it "upside down"

that is, however, the hardest part, the rest of it is a piece of cake. getting the bite point properly adjusted may annoy you for a week, but once it's done, it's done.