Sounds good. One of my boards is running 3.5.2 which isn't ancient yet but I'd like to upgrade. The site has about 10 or so hacks installed. I actually installed all the same hacks on another test board and when I copied and overwrote all the files and tried to run the upgrade of course the site crashed and basically I wiped everything out and started all over.
I opened a thread asking the best way to upgrade a hacked site but the only response I got was someone saying I shouldn't have any problems. Well I did have problems which is why I asked the questions.
Is there an easy way to compare ALL of the files to see which ones have extra code added (hacked) and is there a way to compare the new database with the old database or something?
Like I said my live site with 300+ members needs to go from 3.5.2 to 3.5.4 but I don't want to kill the site. I can back it up which I do every day butam just looking for tips and or tricks to make this whole thing easier!

For instance would it help me if after backing it up I setup the backup in a test environment and try to upgrade that one first and if I succeed move to the live or copy the test over to the live or something?