Can't root a Samsung Tab running 4.0.4 for one reason or another

I think I've tried every site on the net and then some, but for the life of me I can't find any workable instructions to root my Samsung Tab 8.9. It might have something to do with the fact that Android has been updated to 4.0.4, though I don't know. I have tried all sorts, even paying some outfit $35 for a script, but nothing works (and I'm going to get my money back, I don't like wasting cash like that).

I'm not exactly a geek, but not daft either, but I am my wits end. With one site I was supposed to install from 'zip on SDcard' but the trouble is that once in recovery on 4.0.4 that option doesn't seem to exist. It that kind of problem I keep coming up against. So any suggstions? I'll repeat: it's a Samsung Tab (not a Tab 2, note), 8.9 running Android 4.0.4.