Free advice sought on osC contrib installation order

I have inherited an osCommerce installation and have pulled out what little hair I have left trying to get contributions installed - this is due entirely to a number of contributions being already installed on the installation and my completely inadequate knowledge in php to work out what needs to be replaced where in already modified code! So, heres the thing, I have decided that the best course of action is to do a fresh install on a new sub domain, install the various contributions in the correct/recommended order and then move the whole lot to the right domain. The following contributions need to be working on the site, but my post is specifically, what order should they be installed for a newbie like me to be able to work with! STS 4.1 Specific Pricing Per Customer Quantity Price Break Protx Payment Information Pages Enhanced Admin Access v2.2 Newsbox of course if anyone has these installed on an installation already (or even has these plus others installed!) and wants to really help me out I'll glady accept a link to download a zip (hey, you never know unless you ask!) As mentioned, I'm just after some free advice on what order to install them, but please also PM me a bid for actually completing the work for me. Thanks