Highly Modified OS Commerce Search Function

I have a highly modified OSCommerce 2.2 site running on a linux server with a MySQL database. There are 1600 automotive products. Right now there is a search function based on applications that were manually set on each product. We want to remove that function (as easy as emptying a database table) and adding new information. The information will come from the ACES (Aftermarket Catalog Enhanced Standard). I will need the old information backed up (in case the client doesn't like the changes), removed and the new installed. I have attached the files from ACES that include the ACES Data Delivery Specification, XML schema and example, database designs and field definitions for the Vehicle Configuration database (VCdb), the Parts Categorization database (PCdb) and the Qualifier database (Qdb). These will need to be matched with the current inventory of parts so that the search function will work correctly. Right now we have a database table that associates an inventory item with a list of makes and models of vehicles. This in turn populates a drop down search function that retrieves results of items for the web-site user. This can still be used, however, we need to drop the current makes and models and integrate a new list. THE CLIENT WOULD LIKE TO LAUNCH THEIR SITE SEPTEMBER 1ST, 2011!