I've only skimmed the replies so far.
I believe you want to use the old route, which IS steep and starts near Winterscales. The main downside to this route is that it is VERY boggy. The top section collapsed some yeas ago making it a bit of a mud scramble.
To access you follow the main path alongside the viaduct and take the second 'tunnel'. This takes you along a bridal path and into Winterscales, continue on over the cattle grid and past a junction on your left. Now simply watch the wall on your right for a ladder stile. This is the start of the path. It is NOT well defined but essentially goes straight up the hillside. As I've said it is VERY boggy.
Simply keep going straight up. A few meanders mostly to avoid bogs.
The top section is partly fenced off to protect the collapsed old path. When at the top the summit is on your right.
Not a pleasant ascent, but perfectly 'doable'.