I tried this today as well. I was able to get everything but that third bolt on the passenger side and had to put everything back together without changing the plugs. Needless to say, it's a bad design. I guess that's why they advertise to change this out over the 100k miles. Yet, aren't Lexus' supposed to last well over 100K miles? Go figure on why they want to make this so difficult.
Anyhow, it sounds like there is no way to put the bolt back on. Has anyone tried removing the front windshield cowl on the bottom that houses the windshield wipers and upper strut supports? This seems like an option but a lot of work. I'll try to take a better look at this tomorrow.