In my experience the 100 necks are thicker....and wider at the heel.
A couple days ago I played a new Black JS100 at Ken Stanton music in atlanta.....the new trem is nice and works well but the neck is very different than any JS high end models I have ever owned.....and I have had quite a few..LOL
At the moment I have 4 and am working on #5
1000 BP
1 WH
700 mongrel
5 forest
I used to have (stolen in one day)
90th
10th
4 Rainbow
6
1000 bp
and parts parts parts....