Dead easy to do yourself, just dont try to reuse the little split pin thing in the cabin, use a paperclip instead and just bend it so it aint going anywhere. That'll save you about 20 mins of fiddling.
There's a guide on here, and a haynes manual will help
no real need for a guide. cable connects to a rod in the passenger footwell.
just unbolt the metal cover.
in the engine bay theres 1 or 2 10mm bolts that hold the cable to the bulkhead.
cable has a nut and lock nut arrangement. measure the amount of thread showing on the old one to help set up the new one.
pretty obvious where it all goes once you see the new cable