Yeah, you'll find loads of info on Lyell elsewhere.
I wrote about it here, imbedded in another thread:
http://yosemitenews.info/forum/read.php?3,28505,28751#msg-28751Most of the people going up Lyell do it from the canyon itself and
bring crampons and an ice axe. I used and carried neither.
Look at my pictures and you will see why.
You def want to do it from the Lyell-Mac col. With calling yourself
intermediate I honestly think that you will so no way....
Mt. Maclure is easier with many routes that you can build your own.
If you give up on Lyell maybe give that a go. The glacier
has become less of itself over the years. But def. has grown in
recent years so don't just look at the pictures I posted and decide
via them. And certainly do not follow the Hell Hole route.
Have fun and be safe