Here is that line:
This is it looking west from the B2135 around halfway between Steyning and Partridge Green.
Looking east. On the top left corner you may see some radio masts, that is Devils Dyke and just beyond there is the cement works and where the old pylons were.
Here is where they meet the L3's outside Steyning.
And here is where they continue along following the River Adur until they terminate near Bramber. However those terminal towers to the left might actually be their new terminus as the imagery is out of date. You can also see the cement works chimney in the far distance over to the right, that's where the line was.
All the best, Matthew